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

   1 <html>
   2 <head>
   3         <title>BOOST_PP_LIST_IS_NIL</title>
   4         <link rel="stylesheet" type="text/css" href="../styles.css">
   5 </head>
   6 <body>
   7         <div style="margin-left:  0px;">
   8                 The <b>BOOST_PP_LIST_IS_NIL</b> macro is a predicate that determines if a <i>list</i> is nil.
   9         </div>
  10         <h4>Usage</h4>
  11                 <div class="code">
  12                         <b>BOOST_PP_LIST_IS_NIL</b>(<i>list</i>)
  13                 </div>
  14         <h4>Arguments</h4>
  15                 <dl>
  16                         <dt>list</dt>
  17                         <dd>
  18                                 A <i>list</i>.
  19                         </dd>
  20                 </dl>
  21         <h4>Remarks</h4>
  22                 <div>
  23                         If <i>list</i> is nil, this macro expands to <i>1</i>.&nbsp;
  24                         Otherwise, it expands to <i>0</i>.
  25                 </div>
  26         <h4>Requirements</h4>
  27                 <div>
  28                         <b>Header:</b> &nbsp;<a href="../headers/list/adt.html">&lt;boost/preprocessor/list/adt.hpp&gt;</a>
  29                 </div>
  30         <h4>Sample Code</h4>
  31 <div><pre>
  32 #include &lt;<a href="../headers/list/adt.html">boost/preprocessor/list/adt.hpp</a>&gt;
  33
  34 #define LIST (a, <a href="nil.html">BOOST_PP_NIL</a>)
  35
  36 <a href="list_is_nil.html">BOOST_PP_LIST_IS_NIL</a>(LIST) // expands to 0
  37 <a href="list_is_nil.html">BOOST_PP_LIST_IS_NIL</a>(<a href="list_rest.html">BOOST_PP_LIST_REST</a>(LIST)) // expands to 1
  38 </pre></div>
  39         <hr size="1">
  40         <div style="margin-left: 0px;">
  41                 <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
  42                 </br><i>© Copyright Paul Mensonides 2002</i>
  43         </div>
  44         <div style="margin-left: 0px;">
  45                 <p><small>Distributed under the Boost Software License, Version 1.0. (See
  46                 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  47                 copy at <a href=
  48                 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
  49         </div>
  50 </body>
  51 </html>