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

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   3         <title>BOOST_PP_REPEAT_FROM_TO_z</title>
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   8                 The <b>BOOST_PP_REPEAT_FROM_TO_<i>z</i></b> macro represents a reentry into the <b>BOOST_PP_REPEAT_FROM_TO</b> repetition construct.
   9         </div>
  10         <h4>Usage</h4>
  11                 <div class="code">
  12                         <b>BOOST_PP_REPEAT_FROM_TO_</b> ## <i>z</i>(<i>first</i>, <i>last</i>, <i>macro</i>, <i>data</i>)
  13                 </div>
  14         <h4>Arguments</h4>
  15                 <dl>
  16                         <dt>z</dt>
  17                         <dd>
  18                                 The next available <b>BOOST_PP_REPEAT</b> dimension.
  19                         </dd>
  20                         <dt>first</dt>
  21                         <dd>
  22                                 The lower bound of the repetition.&nbsp;
  23                                 Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
  24                         </dd>
  25                         <dt>last</dt>
  26                         <dd>
  27                                 The upper bound of the repetition.
  28                                 Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
  29                         </dd>
  30                         <dt>macro</dt>
  31                         <dd>
  32                                 A ternary operation of the form <i>macro</i>(<i>z</i>, <i>n</i>, <i>data</i>).&nbsp;
  33                                 This macro is expanded by <b>BOOST_PP_REPEAT</b> with the next available repetition depth,
  34                                 the current repetition number, and the auxiliary <i>data</i> argument.&nbsp;
  35                         </dd>
  36                         <dt>data</dt>
  37                         <dd>
  38                                 Auxiliary data passed to <i>macro</i>.
  39                         </dd>
  40                 </dl>
  41         <h4>Remarks</h4>
  42                 <div>
  43                         This macro expands to the sequence:
  44                         <div>
  45                                 <i>macro</i>(<i>z</i>, <i>first</i>, <i>data</i>) <i>macro</i>(<i>z</i>, <i>first</i> + <i>1</i>, <i>data</i>) ... <i>macro</i>(<i>z</i>, <i>last</i> - <i>1</i>, <i>data</i>)
  46                         </div>
  47                 </div>
  48                 <div>
  49                         The number of repetitions (i.e. <i>last</i> - <i>first</i>) must not exceed <b>BOOST_PP_LIMIT_REPEAT</b>.
  50                 </div>
  51                 <div>
  52                         At certain times, it may be necessary to perform the concatenation with <b>BOOST_PP_CAT</b> rather than the preprocessor token-pasting operator.&nbsp;
  53                         This happens when the <i>z</i> value is a macro invocation itself.&nbsp;
  54                         It needs a delay to allow it to expand.&nbsp;
  55                         The syntax in such a scenario becomes:
  56                         <div>
  57                                 <b>BOOST_PP_CAT</b>(<b>BOOST_PP_REPEAT_FROM_TO_</b>, <i>z</i>)(<i>count</i>, <i>macro</i>, <i>data</i>).
  58                         </div>
  59                 </div>
  60         <h4>See Also</h4>
  61                 <ul>
  62                         <li><a href="cat.html">BOOST_PP_CAT</a></li>
  63                         <li><a href="limit_repeat.html">BOOST_PP_LIMIT_REPEAT</a></li>
  64                         <li><a href="repeat.html">BOOST_PP_REPEAT</a></li>
  65                 </ul>
  66         <h4>Requirements</h4>
  67                 <div>
  68                         <b>Header:</b> &nbsp;<a href="../headers/repetition/repeat_from_to.html">&lt;boost/preprocessor/repetition/repeat_from_to.hpp&gt;</a>
  69                 </div>
  70         <h4>Sample Code</h4>
  71 <div><pre>
  72 #include &lt;<a href="../headers/repetition/repeat_from_to.html">boost/preprocessor/repetition/repeat_from_to.hpp</a>&gt;
  73
  74 #define TEXT(z, n, data) n data
  75
  76 #define MACRO(z, n, data) \
  77   ( \
  78      <a href="repeat_from_to_z.html">BOOST_PP_REPEAT_FROM_TO_</a> ## z( \
  79         1, 4, \
  80         TEXT, xyz \
  81      ) \
  82   ) \
  83   /**/
  84
  85 <a href="repeat.html">BOOST_PP_REPEAT</a>(3, MACRO, _)
  86    /*
  87       expands to:
  88       (1 xyz 2 xyz 3 xyz)
  89       (1 xyz 2 xyz 3 xyz)
  90       (1 xyz 2 xyz 3 xyz)
  91    */
  92 </pre></div>
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  95                 <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
  96                 </br><i>© Copyright Paul Mensonides 2002</i>
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  99                 <p><small>Distributed under the Boost Software License, Version 1.0. (See
 100                 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
 101                 copy at <a href=
 102                 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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