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- <title>BOOST_PP_EMPTY</title>
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- The <b>BOOST_PP_EMPTY</b> macro is a nullary utility macro that expands to nothing.
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- <h4>Usage</h4>
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- <b>BOOST_PP_EMPTY</b>()
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- <h4>Remarks</h4>
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- This macro is helps avoid inefficient macro-expansion.
- It is primarily useful as arguments to <b>BOOST_PP_IF</b> or <b>BOOST_PP_IIF</b>.
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- <h4>Requirements</h4>
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- <b>Header:</b> <a href="../headers/facilities/empty.html"><boost/preprocessor/facilities/empty.hpp></a>
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- <h4>Sample Code</h4>
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- #include <<a href="../headers/control/if.html">boost/preprocessor/control/if.hpp</a>>
- #include <<a href="../headers/facilities/empty.html">boost/preprocessor/facilities/empty.hpp</a>>
- #define X() result
- #define MACRO(c) <a href="if.html">BOOST_PP_IF</a>(c, X, <a href="empty.html">BOOST_PP_EMPTY</a>)()
- MACRO(0) // expands to nothing
- MACRO(1) // expands to result
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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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- <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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