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Changed name of macro from BOOST_PP_VARIADIC_OPT to BOOST_PP_VARIADIC_HAS_OPT
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@ -19,17 +19,17 @@ the compilation is at the C++20 level and the __VA_OPT__ construct is supported.
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</dl>
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<h4>Remarks</h4>
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<div>
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When the macro invocation BOOST_PP_VARIADIC_OPT() expands to 1, then this
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When the macro invocation BOOST_PP_VARIADIC_HAS_OPT() expands to 1, then this
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macro exists and can be invoked, otherwise this macro does not exist
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and attempting to invoke it will lead to a preprocessor error that the macro
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can not be found. Because of this condition the header file for including
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this macro includes the header file for the BOOST_PP_VARIADIC_OPT macro.<br>
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this macro includes the header file for the BOOST_PP_VARIADIC_HAS_OPT macro.<br>
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It is possible to pass data to this macro which expands to nothing, in which
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case this macro will expand to 1 just as if nothing has been passed.
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</div>
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<h4>See Also</h4>
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<ul>
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<li><a href="variadic_opt.html">BOOST_PP_VARIADIC_OPT</a></li>
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<li><a href="variadic_opt.html">BOOST_PP_VARIADIC_HAS_OPT</a></li>
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</ul>
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<h4>Requirements</h4>
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<div> <b>Header:</b> <a href="../headers/facilities/check_empty.html"><boost/preprocessor/facilities/check_empty.hpp></a>
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@ -39,7 +39,7 @@ case this macro will expand to 1 just as if nothing has been passed.
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<pre>
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#include <<a href="../headers/facilities/check_empty.html">boost/preprocessor/facilities/check_empty.hpp</a>>
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# if <a href="variadic_opt.html">BOOST_PP_VARIADIC_OPT</a>()
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# if <a href="variadic_opt.html">BOOST_PP_VARIADIC_HAS_OPT</a>()
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#define DATA
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#define OBJECT OBJECT2
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@ -1,15 +1,15 @@
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<html>
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<head>
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<title>BOOST_PP_VARIADIC_OPT</title>
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<title>BOOST_PP_VARIADIC_HAS_OPT</title>
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<link rel="stylesheet" type="text/css" href="../styles.css">
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</head>
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<body>
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<div style="margin-left: 0px;"> The <b>BOOST_PP_VARIADIC_OPT</b> macro
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<div style="margin-left: 0px;"> The <b>BOOST_PP_VARIADIC_HAS_OPT</b> macro
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determines whether or not the C++20 __VA_OPT__ construct is supported for the compiler's preprocessor being used.
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Expands to 1 if the __VA_OPT__ construct is supported, otherwise expands to 0.
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</div>
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<h4>Usage</h4>
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<div class="code"> <b>BOOST_PP_VARIADIC_OPT</b>() <br>
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<div class="code"> <b>BOOST_PP_VARIADIC_HAS_OPT</b>() <br>
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</div>
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<h4>Arguments</h4>
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<dl>
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@ -36,7 +36,7 @@ Expands to 1 if the __VA_OPT__ construct is supported, otherwise expands to 0.
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<div>
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<pre>
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#include <<a href="../headers/variadic/opt.html">boost/preprocessor/variadic/opt.hpp</a>><br>
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#if <a href="variadic_opt.html">BOOST_PP_VARIADIC_OPT</a>()
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#if <a href="variadic_opt.html">BOOST_PP_VARIADIC_HAS_OPT</a>()
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// Preprocessor code which uses __VA_OPT__
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#else
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// Preprocessor code which does not use __VA_OPT__
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@ -47,7 +47,7 @@ or within a macro definition<br><br>
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<pre>
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#include <boost/preprocessor/control/iif.hpp>
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#include <<a href="../headers/variadic/opt.html">boost/preprocessor/variadic/opt.hpp</a>><br>
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#define USE_OPT(...) BOOST_PP_IIF(<a href="variadic_opt.html">BOOST_PP_VARIADIC_OPT</a>(),MACRO_USING_OPT,MACRO_NOT_USING_OPT)(__VA_ARGS__)
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#define USE_OPT(...) BOOST_PP_IIF(<a href="variadic_opt.html">BOOST_PP_VARIADIC_HAS_OPT</a>(),MACRO_USING_OPT,MACRO_NOT_USING_OPT)(__VA_ARGS__)
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#define MACRO_USING_OPT(...) __VA_OPT__( preprocessor tokens ) anything
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#define MACRO_NOT_USING_OPT(...) anything
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</pre>
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