boost-react-native-bundle
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Boost library as in https://sourceforge.net/projects/boost/files/boost/1.57.0/
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<title>BOOST_PP_EXPR_IF</title>
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The <b>BOOST_PP_EXPR_IF</b> macro expands to its second argument if its first argument is non-zero or expands to nothing otherwise.
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<h4>Usage</h4>
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<b>BOOST_PP_EXPR_IF</b>(<i>cond</i>, <i>expr</i>)
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<h4>Arguments</h4>
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<dt>cond</dt>
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The condition that determines if the result is <i>expr</i> or nothing.
Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
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<dt>expr</dt>
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The result of the expansion if <i>cond</i> is non-zero.
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<h4>Remarks</h4>
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This macro performs a boolean conversion on its first argument.
If that conversion is unnecessary, use <b>BOOST_PP_EXPR_IIF</b> instead.
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<h4>See Also</h4>
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<li><a href="expr_iif.html">BOOST_PP_EXPR_IIF</a></li>
<li><a href="limit_mag.html">BOOST_PP_LIMIT_MAG</a></li>
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<h4>Requirements</h4>
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<b>Header:</b> <a href="../headers/control/expr_if.html"><boost/preprocessor/control/expr_if.hpp></a>
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<h4>Sample Code</h4>
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#include <<a href="../headers/control/expr_if.html">boost/preprocessor/control/expr_if.hpp</a>>
#include <<a href="../headers/tuple/elem.html">boost/preprocessor/tuple/elem.hpp</a>>
#define CV(n) \
<a href="expr_if.html">BOOST_PP_EXPR_IF</a>( \
n, \
<a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>( \
4, n, \
(..., const, volatile, const volatile) \
) \
) \
/**/
CV(0) // expands to nothing
CV(1) // expands to const
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<i>� Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
</br><i>� Copyright Paul Mensonides 2002</i>
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<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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