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

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   3         <title>BOOST_PP_LIST_FOR_EACH_I_R</title>
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   8                 The <b>BOOST_PP_LIST_FOR_EACH_I_R</b> macro repeats a macro for each element in a <i>list</i>.&nbsp;
   9                 It reenters <b>BOOST_PP_FOR</b> with maximum efficiency.
  10         </div>
  11         <h4>Usage</h4>
  12                 <div class="code">
  13                         <b>BOOST_PP_LIST_FOR_EACH_I_R</b>(<i>r</i>, <i>macro</i>, <i>data</i>, <i>list</i>)
  14                 </div>
  15         <h4>Arguments</h4>
  16                 <dl>
  17                         <dt>r</dt>
  18                         <dd>
  19                                 The next available <b>BOOST_PP_FOR</b> repetition.
  20                         </dd>
  21                         <dt>macro</dt>
  22                         <dd>
  23                                 A macro of the for <i>macro</i>(<i>r</i>, <i>data</i>, <i>i</i>, <i>elem</i>).&nbsp;
  24                                 This macro is expanded by <b>BOOST_PP_LIST_FOR_EACH_I</b> with each element in <i>list</i>.&nbsp;
  25                                 It is expanded with the next available <b>BOOST_PP_FOR</b> repetition, the auxiliary <i>data</i>, the index of the current element, and the current element.
  26                         </dd>
  27                         <dt>data</dt>
  28                         <dd>
  29                                 Auxiliary data passed to <i>macro</i>.
  30                         </dd>
  31                         <dt>list</dt>
  32                         <dd>
  33                                 The <i>list</i> for which <i>macro</i> will be invoked on each element.
  34                         </dd>
  35                 </dl>
  36         <h4>Remarks</h4>
  37                 <div>
  38                         This macro is a repetition construct.&nbsp;
  39                         If <i>list</i> is (<i>a</i>, (<i>b</i>, (<i>c</i>, <b>BOOST_PP_NIL</b>))), it expands to the sequence:
  40                         <div>
  41                                 <i>macro</i>(<i>r</i>, <i>data</i>, <i>0</i>, <i>a</i>) <i>macro</i>(<i>r</i>, <i>data</i>, <i>1</i>, <i>b</i>) <i>macro</i>(<i>r</i>, <i>data</i>, <i>2</i>, <i>c</i>)
  42                         </div>
  43                 </div>
  44         <h4>See Also</h4>
  45                 <ul>
  46                         <li><a href="list_for_each_i.html">BOOST_PP_LIST_FOR_EACH_I</a></li>
  47                 </ul>
  48         <h4>Requirements</h4>
  49                 <div>
  50                         <b>Header:</b> &nbsp;<a href="../headers/list/for_each_i.html">&lt;boost/preprocessor/list/for_each_i.hpp&gt;</a>
  51                 </div>
  52         <h4>Sample Code</h4>
  53 <div><pre>
  54 #include &lt;<a href="../headers/cat.html">boost/preprocessor/cat.hpp</a>&gt;
  55 #include &lt;<a href="../headers/list/adt.html">boost/preprocessor/list/adt.hpp</a>&gt;
  56 #include &lt;<a href="../headers/list/for_each_i.html">boost/preprocessor/list/for_each_i.hpp</a>&gt;
  57 #include &lt;<a href="../headers/repetition/for.html">boost/preprocessor/repetition/for.hpp</a>&gt;
  58
  59 #define LIST (x, (y, (z, <a href="nil.html">BOOST_PP_NIL</a>)))
  60
  61 #define MACRO_2(r, data, i, elem) <a href="cat.html">BOOST_PP_CAT</a>(elem, i)
  62
  63 #define PRED(r, state) <a href="list_is_cons.html">BOOST_PP_LIST_IS_CONS</a>(state)
  64 #define OP(r, state) <a href="list_rest.html">BOOST_PP_LIST_REST</a>(state)
  65 #define MACRO(r, state) [ <a href="list_for_each_i_r.html">BOOST_PP_LIST_FOR_EACH_I_R</a>(r, MACRO_2, _, state) ]
  66
  67 <a href="for.html">BOOST_PP_FOR</a>(LIST, PRED, OP, MACRO)
  68    // expands to [x0 y1 z2] [y0 z1] [z0]
  69 </pre></div>
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  72                 <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
  73                 </br><i>© Copyright Paul Mensonides 2002</i>
  74         </div>
  75         <div style="margin-left: 0px;">
  76                 <p><small>Distributed under the Boost Software License, Version 1.0. (See
  77                 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  78                 copy at <a href=
  79                 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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