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

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   3         <title>BOOST_PP_ENUM</title>
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   8                 The <b>BOOST_PP_ENUM</b> macro generates a comma-separated list.
   9         </div>
  10         <h4>Usage</h4>
  11                 <div class="code">
  12                         <b>BOOST_PP_ENUM</b>(<i>count</i>, <i>macro</i>, <i>data</i>)
  13                 </div>
  14         <h4>Arguments</h4>
  15                 <dl>
  16                         <dt>count</dt>
  17                         <dd>
  18                                 The number of repetitious calls to <i>macro</i>.&nbsp;
  19                                 Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_REPEAT</b>.
  20                         </dd>
  21                         <dt>macro</dt>
  22                         <dd>
  23                                 A ternary operation of the form <i>macro</i>(<i>z</i>, <i>n</i>, <i>data</i>).&nbsp;
  24                                 This macro is expanded by <b>BOOST_PP_ENUM</b> with the next available repetition depth,
  25                                 the current repetition number, and the auxiliary <i>data</i> argument.&nbsp;
  26                         </dd>
  27                         <dt>data</dt>
  28                         <dd>
  29                                 Auxiliary data passed to <i>macro</i>.
  30                         </dd>
  31                 </dl>
  32         <h4>Remarks</h4>
  33                 <div>
  34                         This macro expands to the comma-separated sequence:
  35                         <div>
  36                                 <i>macro</i>(<i>z</i>, <i>0</i>, <i>data</i>), <i>macro</i>(<i>z</i>, <i>1</i>, <i>data</i>), ... <i>macro</i>(<i>z</i>, <i>count</i> - <i>1</i>, <i>data</i>)
  37                         </div>
  38                 </div>
  39                 <div>
  40                         The <i>z</i> value that is passed to <i>macro</i> represents the next available repetition dimension.&nbsp;
  41                         Other macros that have <b>_Z</b> suffix variants internally use <b>BOOST_PP_REPEAT</b>--for example, <b>BOOST_PP_ENUM_PARAMS</b> and <b>BOOST_PP_ENUM_PARAMS_Z</b>.&nbsp;
  42                         Using these <b>_Z</b> versions is not strictly necessary, but passing the <i>z</i> value (that is passed to <i>macro</i>) to these macros allows them to reenter <b>BOOST_PP_REPEAT</b> with maximum efficiency.
  43                 </div>
  44                 <div>
  45                         To directly use this <i>z</i> value, rather than simply passing it to another macro, see <b>BOOST_PP_ENUM_<i>z</i></b>.
  46                 </div>
  47                 <div>
  48                         Previously, this macro could not be used recursively inside <b>BOOST_PP_REPEAT</b>.&nbsp;
  49                         This limitation no longer exists, as the library can automatically detect the next available repetition depth.
  50                 </div>
  51         <h4>See Also</h4>
  52                 <ul>
  53                         <li><a href="enum_z.html">BOOST_PP_ENUM_<i>z</i></a></li>
  54                         <li><a href="limit_repeat.html">BOOST_PP_LIMIT_REPEAT</a></li>
  55                 </ul>
  56         <h4>Requirements</h4>
  57                 <div>
  58                         <b>Header:</b> &nbsp;<a href="../headers/repetition/enum.html">&lt;boost/preprocessor/repetition/enum.hpp&gt;</a>
  59                 </div>
  60         <h4>Sample Code</h4>
  61 <div><pre>
  62 #include &lt;<a href="../headers/repetition/enum.html">boost/preprocessor/repetition/enum.hpp</a>&gt;
  63
  64 #define TEXT(z, n, text) text
  65
  66 <a href="enum.html">BOOST_PP_ENUM</a>(4, TEXT, class) // expands to class, class, class, class
  67 </pre></div>
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  70                 <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
  71                 </br><i>© Copyright Paul Mensonides 2002</i>
  72         </div>
  73         <div style="margin-left: 0px;">
  74                 <p><small>Distributed under the Boost Software License, Version 1.0. (See
  75                 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  76                 copy at <a href=
  77                 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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