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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> |
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| <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> |
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| <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> |
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| <h4>Sample Code</h4> |
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| <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>#define MACRO_ADD_NUMBERS(...) <a href="overload.html">BOOST_PP_OVERLOAD</a>(MACRO_,__VA_ARGS__)(__VA_ARGS__)<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>MACRO_ADD_NUMBERS(5) // output is 15<br>MACRO_ADD_NUMBERS(3,6) // output is 9<br></pre> |
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| <div style="margin-left: 0px;"> <i></i><i>© Copyright Edward Diener 2011,2013</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> |
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