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

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   8     <div style="margin-left:  0px;"> The <b>BOOST_PP_IS_BEGIN_PAREN</b>S
   9       determines whether the input starts with a set of parenthesis.</div>
  10     <h4>Usage</h4>
  11     <div class="code"> <b>BOOST_PP_IS_BEGIN_PARENS</b>(...) <a href="../topics/variadic_macros.html#VNotation"
  12         target="_self"><sup>(v)</sup></a></div>
  13     <h4>Arguments</h4>
  14     <h4>&nbsp;&nbsp;&nbsp; ...&nbsp;&nbsp;&nbsp; <span style="font-weight: normal;">&nbsp;&nbsp;&nbsp;
  15         &nbsp;&nbsp;&nbsp; The input as variadic data.</span></h4>
  16     <h4>Remarks</h4>
  17     <div> If the input input begins with a parenthesis, with any data within
  18       that parenthesis, the macro returns 1, otherwise it returns 0. Data may
  19       follow the beginning parenthesis and the macro still will return 1.<br>
  20       <br>
  21       For Visual Studio 2005 ( VC8 ) the input data must be a single parameter
  22       else a compilation error will occur.</div>
  23     <h4>See Also</h4>
  24     <ul>
  25       <li><a href="remove_parens.html">BOOST_PP_REMOVE_PARENS</a></li>
  26     </ul>
  27     <h4>Requirements</h4>
  28     <div> <b>Header:</b> &nbsp;<a href="../headers/punctuation/is_begin_parens.html">&lt;boost/preprocessor/punctuation/is_begin_parens.hpp&gt;</a>
  29     </div>
  30     <h4>Sample Code</h4>
  31     <div>
  32       <pre>#include &lt;<a href="../headers/punctuation/is_begin_parens.html">boost/preprocessor/punctuation/is_begin_parens.hpp</a>&gt;
  33
  34 #define VARDATA more_data , more_params<br>#define VARDATAP ( data ) more_data , more_params<br>#define DATA data<br>#define DATAP ( data ) more_data<br>
  35 BOOST_PP_IS_BEGIN_PARENS(VARDATA)  // expands to 0, compiler error with VC8
  36 BOOST_PP_IS_BEGIN_PARENS(VARDATAP) // expands to 1, compiler error with VC8<br><br>BOOST_PP_IS_BEGIN_PARENS(DATA)     // expands to 0
  37 BOOST_PP_IS_BEGIN_PARENS(DATAP)    // expands to 1<br><br>BOOST_PP_IS_BEGIN_PARENS()         // expands to 0<br>
  38 </pre></div>
  39     <hr size="1">
  40     <div style="margin-left: 0px;"> <i>© Copyright Edward Diener 2014</i> </div>
  41     <div style="margin-left: 0px;">
  42       <p><small>Distributed under the Boost Software License, Version 1.0. (See
  43           accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a>
  44           or 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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