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

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   3         <title>BOOST_PP_ITERATE</title>
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   8                 The <b>BOOST_PP_ITERATE</b> macro initiates a <i>file-iteration</i>.
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  10         <h4>Usage</h4>
  11                 <div class="code">
  12                         #include <b>BOOST_PP_ITERATE</b>()
  13                 </div>
  14         <h4>Remarks</h4>
  15                 <div>
  16                         Arguments to this macro are passed as <i>external named arguments</i> in one of two
  17                         ways--either through <b>BOOST_PP_FILENAME_<i>x</i></b> and <b>BOOST_PP_ITERATION_LIMITS</b> <i>or</i>
  18                         through <b>BOOST_PP_ITERATION_PARAMS_<i>x</i></b>.&nbsp;
  19                 </div>
  20                 <div>
  21                         Three pieces of information are required to perform a <i>file-iteration</i>.&nbsp;
  22                         First, the name of a file to iterate over.&nbsp;
  23                         This is passed via <b>BOOST_PP_FILENAME_<i>x</i></b> <i>or</i> as part of <b>BOOST_PP_ITERATION_PARAMS_<i>x</i></b>.&nbsp;
  24                         The <i>file-iteration</i> mechanism will repeatedly include this file with iteration values ranging from a lower bound to an upper bound--the second and third <i>required</i> parameters.&nbsp;
  25                         These two boundaries are either passed through <b>BOOST_PP_ITERATION_LIMITS</b> <i>or</i> as part of <b>BOOST_PP_ITERATION_PARAMS_<i>x</i></b>.
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  28                         Optionally, a fourth parameter may be passed that associates flags with an iteration.&nbsp;
  29                         These flags are primarily useful to distinguish one iteration from another in the same file.&nbsp;
  30                         This parameter can only be passed through <b>BOOST_PP_ITERATION_PARAMS_<i>x</i></b>.
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  32                 <div>
  33                         While a <i>file-iteration</i> is in progress, <b>BOOST_PP_IS_ITERATING</b> is defined as <i>1</i>.
  34                 </div>
  35         <h4>See Also</h4>
  36                 <ul>
  37                         <li><a href="filename_x.html">BOOST_PP_FILENAME_<i>x</i></a></li>
  38                         <li><a href="is_iterating.html">BOOST_PP_IS_ITERATING</a></li>
  39                         <li><a href="iteration_limits.html">BOOST_PP_ITERATION_LIMITS</a></li>
  40                         <li><a href="iteration_params_x.html">BOOST_PP_ITERATION_PARAMS_<i>x</i></a></li>
  41                 </ul>
  42         <h4>Requirements</h4>
  43                 <div>
  44                         <b>Header:</b> &nbsp;<a href="../headers/iteration/iterate.html">&lt;boost/preprocessor/iteration/iterate.hpp&gt;</a>
  45                 </div>
  46         <h4>Sample Code</h4>
  47 <div><pre>
  48 // file.h
  49 #if !<a href="is_iterating.html">BOOST_PP_IS_ITERATING</a>
  50
  51    #ifndef FILE_H_
  52    #define FILE_H_
  53
  54    #include &lt;<a href="../headers/iteration/iterate.html">boost/preprocessor/iteration/iterate.hpp</a>&gt;
  55
  56    #define <a href="iteration_params_x.html">BOOST_PP_ITERATION_PARAMS_1</a> (3, (1, 10, "file.h"))
  57    #include <a href="iterate.html">BOOST_PP_ITERATE</a>()
  58
  59    #define <a href="filename_x.html">BOOST_PP_FILENAME_1</a> "file.h"
  60    #define <a href="iteration_limits.html">BOOST_PP_ITERATION_LIMITS</a> (11, 20)
  61    #include <a href="iterate.html">BOOST_PP_ITERATE</a>()
  62
  63    #endif
  64
  65 #else
  66
  67    current iteration value is <a href="iteration.html">BOOST_PP_ITERATION</a>()
  68
  69 #endif
  70 </pre></div>
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  73                 <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
  74                 </br><i>© Copyright Paul Mensonides 2002</i>
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  76         <div style="margin-left: 0px;">
  77                 <p><small>Distributed under the Boost Software License, Version 1.0. (See
  78                 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  79                 copy at <a href=
  80                 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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