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

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   3         <title>BOOST_PP_LIST_FOR_EACH_PRODUCT</title>
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   8                 The <b>BOOST_PP_LIST_FOR_EACH_PRODUCT</b> macro repeats a macro for each cartesian product of several <i>lists</i>.
   9         </div>
  10         <h4>Usage</h4>
  11                 <div class="code">
  12                         <b>BOOST_PP_LIST_FOR_EACH_PRODUCT</b>(<i>macro</i>, <i>size</i>, <i>tuple</i>)
  13                 </div>
  14         <h4>Arguments</h4>
  15                 <dl>
  16                         <dt>macro</dt>
  17                         <dd>
  18                                 The binary macro of the form <i>macro</i>(<i>r</i>, <i>product</i>).&nbsp;
  19                                 This macro is expanded by <b>BOOST_PP_FOR_EACH_PRODUCT</b> with each cartesian product in <i>tuple</i>.&nbsp;
  20                                 It is expanded with the next available <b>BOOST_PP_FOR</b> repetition and a <i>tuple</i> containing a cartesian product.&nbsp;
  21                                 This <i>tuple</i> will have <i>size</i> elements.
  22                         </dd>
  23                         <dt>size</dt>
  24                         <dd>
  25                                 The size of <i>tuple</i>.
  26                         </dd>
  27                         <dt>tuple</dt>
  28                         <dd>
  29                                 A <i>tuple</i> of <i>lists</i> from which cartesian products are obtained.
  30                         </dd>
  31                 </dl>
  32         <h4>Remarks</h4>
  33                 <div>
  34                         This macro is a repetition construct.&nbsp;
  35                         If two <i>lists</i> are (<i>a</i>, (<i>b</i>, (<i>c</i>, <b>BOOST_PP_NIL</b>))) and (<i>x</i>, (<i>y</i>, (<i>z</i>, <b>BOOST_PP_NIL</b>))),
  36                         this macro will produce the following sequence:
  37                         <div>
  38                                 <i>macro</i>(<i>r</i>, (<i>a</i>, <i>x</i>))
  39                                 <i>macro</i>(<i>r</i>, (<i>a</i>, <i>y</i>))
  40                                 <i>macro</i>(<i>r</i>, (<i>a</i>, <i>z</i>))<br>
  41                                 <i>macro</i>(<i>r</i>, (<i>b</i>, <i>x</i>))
  42                                 <i>macro</i>(<i>r</i>, (<i>b</i>, <i>y</i>))
  43                                 <i>macro</i>(<i>r</i>, (<i>b</i>, <i>z</i>))<br>
  44                                 <i>macro</i>(<i>r</i>, (<i>c</i>, <i>x</i>))
  45                                 <i>macro</i>(<i>r</i>, (<i>c</i>, <i>y</i>))
  46                                 <i>macro</i>(<i>r</i>, (<i>c</i>, <i>z</i>))
  47                         </div>
  48                 </div>
  49                 <div>
  50                         Previously, this macro could not be used inside <b>BOOST_PP_FOR</b>.&nbsp;
  51                         There is no longer any such restriction.&nbsp;
  52                         It is more efficient, however, to use <b>BOOST_PP_LIST_FOR_EACH_PRODUCT_R</b> in such a situation.
  53                 </div>
  54         <h4>See Also</h4>
  55                 <ul>
  56                         <li><a href="list_for_each_product_r.html">BOOST_PP_LIST_FOR_EACH_PRODUCT_R</a></li>
  57                 </ul>
  58         <h4>Requirements</h4>
  59                 <div>
  60                         <b>Header:</b> &nbsp;<a href="../headers/list/for_each_product.html">&lt;boost/preprocessor/list/for_each_product.hpp&gt;</a>
  61                 </div>
  62         <h4>Sample Code</h4>
  63 <div><pre>
  64 #include &lt;<a href="../headers/list/for_each_product.html">boost/preprocessor/list/for_each_product.hpp</a>&gt;
  65
  66 #define L1 (a, (b, (c, <a href="nil.html">BOOST_PP_NIL</a>)))
  67 #define L2 (x, (y, (z, <a href="nil.html">BOOST_PP_NIL</a>)))
  68
  69 #define MACRO(r, product) product
  70
  71 <a href="list_for_each_product.html">BOOST_PP_LIST_FOR_EACH_PRODUCT</a>(MACRO, 2, (L1, L2))
  72    // expands to (a, x) (a, y) (a, z) (b, x) (b, y) (b, z) (c, x) (c, y) (c, z)
  73 </pre></div>
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  76                 <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
  77                 </br><i>© Copyright Paul Mensonides 2002</i>
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  79         <div style="margin-left: 0px;">
  80                 <p><small>Distributed under the Boost Software License, Version 1.0. (See
  81                 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  82                 copy at <a href=
  83                 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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