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

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   3         <title>BOOST_PP_LIST_CONS</title>
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   8                 The <b>BOOST_PP_LIST_CONS</b> macro is a <i>list</i> constructor.
   9         </div>
  10         <h4>Usage</h4>
  11                 <div class="code">
  12                         <b>BOOST_PP_LIST_CONS</b>(<i>head</i>, <i>tail</i>)
  13                 </div>
  14         <h4>Arguments</h4>
  15                 <dl>
  16                         <dt>head</dt>
  17                         <dd>
  18                                 An element in a <i>list</i>.
  19                         </dd>
  20                         <dt>tail</dt>
  21                         <dd>
  22                                 Either a <i>list</i>, <b>BOOST_PP_LIST_NIL</b>, or <b>BOOST_PP_NIL</b>.
  23                         </dd>
  24                 </dl>
  25         <h4>Remarks</h4>
  26                 <div>
  27                         This macro appends a new head to an existing <i>list</i> or creates a <i>list</i> from <b>BOOST_PP_LIST_NIL</b>.
  28                 </div>
  29                 <div>
  30                         This macro is no longer necessary.&nbsp;
  31                         For example...
  32                         <div>
  33                                 <b>BOOST_PP_LIST_CONS</b>(a, <b>BOOST_PP_LIST_CONS</b>(b, <b>BOOST_PP_LIST_NIL</b>)))
  34                         </div>
  35                         ...is just an explicit way of writing the following:
  36                         <div>
  37                                 (a, (b, <b>BOOST_PP_NIL</b>))
  38                         </div>
  39                         Because of this, this macro is deprecated.
  40                 </div>
  41         <h4>See Also</h4>
  42                 <ul>
  43                         <li><a href="list_nil.html">BOOST_PP_LIST_NIL</a></li>
  44                         <li><a href="nil.html">BOOST_PP_NIL</a></li>
  45                 </ul>
  46         <h4>Requirements</h4>
  47                 <div>
  48                         <b>Header:</b> &nbsp;<a href="../headers/list/adt.html">&lt;boost/preprocessor/list/adt.hpp&gt;</a>
  49                 </div>
  50         <h4>Sample Code</h4>
  51 <div><pre>
  52 #include &lt;<a href="../headers/list/adt.html">boost/preprocessor/list/adt.hpp</a>&gt;
  53
  54 #define OLD \
  55    <a href="list_cons.html">BOOST_PP_LIST_CONS</a>( \
  56       a, \
  57       <a href="list_cons.html">BOOST_PP_LIST_CONS</a>( \
  58          b, \
  59          <a href="list_cons.html">BOOST_PP_LIST_CONS</a>( \
  60             c, \
  61             <a href="list_nil.html">BOOST_PP_LIST_NIL</a> \
  62          ) \
  63       ) \
  64    ) \
  65    /**/
  66
  67 #define NEW (a, (b, (c, <a href="nil.html">BOOST_PP_NIL</a>)))
  68
  69 <a href="list_first.html">BOOST_PP_LIST_FIRST</a>(OLD) == <a href="list_first.html">BOOST_PP_LIST_FIRST</a>(NEW)
  70    // expands to a == a
  71
  72 <a href="list_rest.html">BOOST_PP_LIST_REST</a>(OLD) == <a href="list_rest.html">BOOST_PP_LIST_REST</a>(NEW)
  73    // expands to (b, (c, <a href="nil.html">BOOST_PP_NIL</a>)) == (b, (c, <a href="nil.html">BOOST_PP_NIL</a>))
  74 </pre></div>
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  77                 <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
  78                 </br><i>© Copyright Paul Mensonides 2002</i>
  79         </div>
  80         <div style="margin-left: 0px;">
  81                 <p><small>Distributed under the Boost Software License, Version 1.0. (See
  82                 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  83                 copy at <a href=
  84                 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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