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

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   3         <title>BOOST_PP_RELATIVE_ITERATION</title>
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   8                 The <b>BOOST_PP_RELATIVE_ITERATION</b> macro expands to the iteration value of a <i>file-iteration</i> depth relative to the current depth.
   9         </div>
  10         <h4>Usage</h4>
  11                 <div class="code">
  12                         <b>BOOST_PP_RELATIVE_ITERATION</b>(<i>i</i>)
  13                 </div>
  14         <h4>Arguments</h4>
  15                 <dl>
  16                         <dt>i</dt>
  17                         <dd>
  18                                 The relative depth of the frame whose iteration value is to be retreived.&nbsp;
  19                                 Valid values range from <i>0</i> to <b>BOOST_PP_ITERATION_DEPTH</b>() - <i>1</i>.
  20                         </dd>
  21                 </dl>
  22         <h4>Remarks</h4>
  23                 <div>
  24                         This macro is only valid when a <i>file-iteration</i> is in progress.
  25                 </div>
  26                 <div>
  27                         The argument <i>i</i> is interpreted as the number of frames <i>outward</i> from the current frame.&nbsp;
  28                         Therefore, <b>BOOST_PP_RELATIVE_ITERATION</b>(<i>0</i>) is equivalent to <b>BOOST_PP_ITERATION</b>().
  29                 </div>
  30         <h4>Requirements</h4>
  31                 <div>
  32                         <b>Header:</b> &nbsp;<a href="../headers/iteration/iterate.html">&lt;boost/preprocessor/iteration/iterate.hpp&gt;</a>
  33                 </div>
  34         <h4>Sample Code</h4>
  35 <div><pre>
  36 // file.h
  37 #if !<a href="is_iterating.html">BOOST_PP_IS_ITERATING</a>
  38
  39    #ifndef FILE_H_
  40    #define FILE_H_
  41
  42    #include &lt;<a href="../headers/iteration/iterate.html">boost/preprocessor/iteration/iterate.hpp</a>&gt;
  43
  44 1st iteration:
  45    #define <a href="iteration_params_x.html">BOOST_PP_ITERATION_PARAMS_1</a> (4, (0, 3, "file.h", 0x0001))
  46    #include <a href="iterate.html">BOOST_PP_ITERATE</a>()
  47
  48 2nd iteration:
  49    #define <a href="iteration_params_x.html">BOOST_PP_ITERATION_PARAMS_1</a> (4, (1, 10, "file.h", 0x0002))
  50    #include <a href="iterate.html">BOOST_PP_ITERATE</a>()
  51
  52    #endif
  53
  54 #elif <a href="iteration_depth.html">BOOST_PP_ITERATION_DEPTH</a>() == 1 \
  55    &amp;&amp; <a href="iteration_flags.html">BOOST_PP_ITERATION_FLAGS</a>() == 0x0001 \
  56    /**/
  57
  58    --
  59    #define <a href="iteration_params_x.html">BOOST_PP_ITERATION_PARAMS_2</a> (3, (1, 10, "file.h"))
  60    #include <a href="iterate.html">BOOST_PP_ITERATE</a>()
  61
  62 #elif <a href="iteration_depth.html">BOOST_PP_ITERATION_DEPTH</a>() == 1 \
  63    &amp;&amp; <a href="iteration_flags.html">BOOST_PP_ITERATION_FLAGS</a>() == 0x0002 \
  64    /**/
  65
  66    --
  67    #define <a href="iteration_params_x.html">BOOST_PP_ITERATION_PARAMS_2</a> \
  68       (3, (1, <a href="iteration.html">BOOST_PP_ITERATION</a>(), "file.h")) \
  69       /**/
  70    #include <a href="iterate.html">BOOST_PP_ITERATE</a>()
  71
  72 #elif <a href="iteration_depth.html">BOOST_PP_ITERATION_DEPTH</a>() == 2 \
  73    &amp;&amp; <a href="frame_flags.html">BOOST_PP_FRAME_FLAGS</a>(1) == 0x0001 \
  74    /**/
  75
  76    --
  77    #define <a href="iteration_params_x.html">BOOST_PP_ITERATION_PARAMS_3</a> \
  78       (3, (1, <a href="iteration.html">BOOST_PP_ITERATION</a>(), "file.h")) \
  79       /**/
  80    #include <a href="iterate.html">BOOST_PP_ITERATE</a>()
  81
  82 #else // used by both
  83
  84    previous: <a href="relative_iteration.html">BOOST_PP_RELATIVE_ITERATION</a>(1)
  85    current: <a href="iteration.html">BOOST_PP_ITERATION</a>()
  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>
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  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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