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

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   2 <head>
   3         <title>BOOST_PP_INCLUDE_SELF</title>
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   8                 The <b>BOOST_PP_INCLUDE_SELF</b> macro includes a file indirectly.
   9         </div>
  10         <h4>Usage</h4>
  11                 <div class="code">
  12                         #include <b>BOOST_PP_INCLUDE_SELF</b>()
  13                 </div>
  14         <h4>Arguments</h4>
  15                 <dl>
  16                         <dt>filename</dt>
  17                         <dd>
  18                                 A quoted or angle-bracketed filename to be included by <b>BOOST_PP_INCLUDE_SELF</b>.
  19                         </dd>
  20                 </dl>
  21         <h4>Remarks</h4>
  22                 <div>
  23                         <b>BOOST_PP_INDIRECT_SELF</b> must be defined prior to using this macro.
  24                 </div>
  25                 <div>
  26                         Most preprocessors will not allow a file to directly include itself--even when the file protects itself from such a scenario.&nbsp;
  27                         This macro, in combination with <b>BOOST_PP_INDIRECT_SELF</b> allows a file to include itself indirectly.
  28                 </div>
  29                 <div>
  30                         While <b>BOOST_PP_INDIRECT_SELF</b> is being included, <b>BOOST_PP_INCLUDE_SELF</b> defines the macro <b>BOOST_PP_IS_SELFISH</b> to <i>1</i>.&nbsp;
  31                         When it returns from the inclusion, <b>BOOST_PP_IS_SELFISH</b> is undefined.
  32                 </div>
  33         <h4>See Also</h4>
  34                 <ul>
  35                         <li><a href="indirect_self.html">BOOST_PP_INDIRECT_SELF</a></li>
  36                         <li><a href="is_selfish.html">BOOST_PP_IS_SELFISH</a></li>
  37                 </ul>
  38         <h4>Requirements</h4>
  39                 <div>
  40                         <b>Header:</b> &nbsp;<a href="../headers/iteration/self.html">&lt;boost/preprocessor/iteration/self.hpp&gt;</a>
  41                 </div>
  42         <h4>Sample Code</h4>
  43 <div><pre>
  44 // file.h
  45 #if !<a href="is_selfish.html">BOOST_PP_IS_SELFISH</a>
  46
  47    #ifndef FILE_H_
  48    #define FILE_H_
  49
  50    #include &lt;<a href="../headers/iteration/self.html">boost/preprocessor/iteration/self.hpp</a>&gt;
  51
  52    #define NAME X
  53    struct NAME {
  54       // ...
  55       #define <a href="indirect_self.html">BOOST_PP_INDIRECT_SELF</a> "file.h"
  56       #include <a href="include_self.html">BOOST_PP_INCLUDE_SELF</a>()
  57    };
  58
  59    #define NAME Y
  60    struct NAME {
  61       // ...
  62       #define <a href="indirect_self.html">BOOST_PP_INDIRECT_SELF</a> "file.h"
  63       #include <a href="include_self.html">BOOST_PP_INCLUDE_SELF</a>()
  64    };
  65
  66    #define NAME Z
  67    struct NAME {
  68       // ...
  69       #define <a href="indirect_self.html">BOOST_PP_INDIRECT_SELF</a> "file.h"
  70       #include <a href="include_self.html">BOOST_PP_INCLUDE_SELF</a>()
  71    };
  72
  73    #endif
  74
  75 #else
  76
  77       inline bool validate(NAME* p) {
  78          return true;
  79       }
  80
  81       template&lt;class T&gt; bool validate(T* p) {
  82          return dynamic_cast&lt;NAME*&gt;(p);
  83       }
  84
  85    #undef NAME
  86
  87 #endif
  88 </pre></div>
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  91                 <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
  92                 </br><i>© Copyright Paul Mensonides 2002</i>
  93         </div>
  94         <div style="margin-left: 0px;">
  95                 <p><small>Distributed under the Boost Software License, Version 1.0. (See
  96                 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  97                 copy at <a href=
  98                 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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