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

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   3     <title>BOOST_PP_TUPLE_EAT</title>
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   8                 The <b>BOOST_PP_TUPLE_EAT</b> macro expands to a macro that eats a <i>tuple</i>.
   9         </div>
  10         <h4>Usage</h4>
  11                 <div class="code">
  12                         <b>BOOST_PP_TUPLE_EAT</b>(<i>size</i>)<br>
  13 <br>
  14 or<br>
  15 <br>
  16 <b>BOOST_PP_TUPLE_EAT</b>(<i>size</i>) <a href="../topics/variadic_macros.html#VNotation" target="_self"><sup>(v)</sup></a><b></b><br>
  17 </div>
  18         <h4>Arguments</h4>
  19                 <dl>
  20                         <dt>size</dt>
  21                         <dd>
  22                                 The size of the <i>tuple</i> to be eaten.&nbsp;
  23                                 Valid <i>tuple</i> sizes range from <i>1</i> to <b>BOOST_PP_LIMIT_TUPLE</b>.
  24                         </dd>
  25                 </dl>
  26         <h4>Remarks</h4>
  27                 <div>
  28                         The <i>size</i> argument must be the actual size of the <i>tuple</i> in the non-variadic version. <br>
  29 <br>For the variadic version <a href="../topics/variadic_macros.html#VNotation" target="_self"><sup>(v)</sup></a>&nbsp;the
  30 size may be left out
  31 completely so that the macro can be invoked as BOOST_PP_TUPLE_EAT(); you may get a warning from some compilers, but the
  32 functionality will still work. If you specify a size in the variadic
  33 version, it will be ignored, but the warning from some compilers will
  34 not occur.<br>
  35  </div>
  36         <h4>See Also</h4>
  37                 <ul>
  38                         <li><a href="limit_tuple.html">BOOST_PP_LIMIT_TUPLE</a></li>
  39                 </ul>
  40         <h4>Requirements</h4>
  41                 <div>
  42                         <b>Header:</b> &nbsp;<a href="../headers/tuple/eat.html">&lt;boost/preprocessor/tuple/eat.hpp&gt;</a>
  43                 </div>
  44         <h4>Sample Code</h4>
  45 <div><pre>#include &lt;<a href="../headers/control/if.html">boost/preprocessor/control/if.hpp</a>&gt;<br>#include &lt;<a href="../headers/tuple/eat.html">boost/preprocessor/tuple/eat.hpp</a>&gt;<br><br>#define OP(a, b) (a b)<br><br>#define MACRO(n) <a href="if.html">BOOST_PP_IF</a>(n, OP, <a href="tuple_eat.html">BOOST_PP_TUPLE_EAT</a>(2))(1, 2)<br><br>// or for the variadic version <a href="../topics/variadic_macros.html#VNotation" target="_self"><sup>(v)</sup></a><br><br>#define MACRO(n) <a href="if.html">BOOST_PP_IF</a>(n, OP, <a href="file:///C:/Programming/VersionControl/sandbox/variadics/libs/preprocessor/doc/ref/tuple_eat.html">BOOST_PP_TUPLE_EAT</a>())(1, 2)<br><br>MACRO(0) // expands to nothing<br>MACRO(1) // expands to (1, 2)<br></pre></div>
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  48                 <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
  49                 <br><i>© Copyright Paul Mensonides 2002<br>
  50 </i><i>© Copyright Edward Diener 2011,2013</i><br>
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  52         <div style="margin-left: 0px;">
  53                 <p><small>Distributed under the Boost Software License, Version 1.0. (See
  54                 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  55                 copy at <a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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