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- <title>BOOST_PP_OVERLOAD</title>
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- <div style="margin-left: 0px;"> The <b>BOOST_PP_OVERLOAD</b> variadic
- macro expands to the name of a non-variadic macro having a given number of
- parameters.<br>
- </div>
- <h4>Usage</h4>
- <div class="code"> <b>BOOST_PP_OVERLOAD</b>(<i>prefix</i>,...) <a href="../topics/variadic_macros.html#VNotation"
- target="_self"><sup>(v)</sup></a><br>
- </div>
- <h4>Arguments</h4>
- <dl>
- <dt>prefix<br>
- </dt>
- <dd> The prefix of the non-variadic macro name. </dd>
- <dt>...<br>
- </dt>
- <dd><i> Variadic data</i>. The number of variadic data
- elements, as determined by BOOST_PP_VARIADIC_SIZE, is appended to the
- prefix to form the output non-variadic macro name.<br>
- </dd>
- </dl>
- <h4>Remarks</h4>
- <div> This macro creates a macro name which depends on the number of
- elements of variadic data. It should be used in the form of <br>
- BOOST_PP_OVERLOAD(MACRO_NAME_,__VA_ARGS__)(__VA_ARGS__) in order to
- call a non-variadic macro taking a given number of variadic data
- elements as non-variadic arguments. In this way one can invoke a
- variadic macro with a variable number of parameters which calls one of
- a series of non-variadic macros doing very similar things.
- </div>
- <b>Requirements</b>
- <div> <b>Header:</b> <a href="../headers/facilities/overload.html"><boost/preprocessor/facilities/overload.hpp></a>
- </div>
- <h4>Sample Code</h4>
- <div>
- <pre>#include <<a href="../headers/facilities/overload.html">boost/preprocessor/facilities/overload.hpp</a>><br>#include <<a
- href="../headers/cat.html">boost/preprocessor/cat.hpp</a>><br>#include <<a href="../headers/facilities/empty.html">boost/preprocessor/facilities/empty.hpp</a>><br>#include <<a
- href="../headers/arithmetic/add.html">boost/preprocessor/arithmetic/add.hpp</a>><br><br>#define MACRO_1(number) MACRO_2(number,10)<br>#define MACRO_2(number1,number2) <a
- href="add.html">BOOST_PP_ADD</a>(number1,number2)<br><br>#if !BOOST_PP_VARIADICS_MSVC<br><br>#define MACRO_ADD_NUMBERS(...) <a
- href="overload.html">BOOST_PP_OVERLOAD</a>(MACRO_,__VA_ARGS__)(__VA_ARGS__)<br><br>#else<br><br>// or for Visual C++<br><br>#define MACRO_ADD_NUMBERS(...) \<br> <a
- href="cat.html">BOOST_PP_CAT</a>(<a href="overload.html">BOOST_PP_OVERLOAD</a>(MACRO_,__VA_ARGS__)(__VA_ARGS__),<a
- href="empty.html">BOOST_PP_EMPTY</a>())<br><br>#endif<br><br>MACRO_ADD_NUMBERS(5) // output is 15<br>MACRO_ADD_NUMBERS(3,6) // output is 9</pre>
- </div>
- <hr size="1">
- <div style="margin-left: 0px;"> <i></i><i>© Copyright Edward Diener 2011,2013,2016</i> </div>
- <div style="margin-left: 0px;">
- <p><small>Distributed under the Boost Software License, Version 1.0.
- (See accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a>
- or copy at <a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
- </div>
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