| 1 | <html> |
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| 2 | <head> |
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| 3 | <title>BOOST_PP_IIF</title> |
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| 4 | <link rel="stylesheet" type="text/css" href="../styles.css"> |
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| 5 | </head> |
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| 6 | <body> |
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| 7 | <div style="margin-left: 0px;"> |
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| 8 | The <b>BOOST_PP_IIF</b> macro chooses between to values based on a bitwise condition. |
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| 9 | </div> |
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| 10 | <h4>Usage</h4> |
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| 11 | <div class="code"> |
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| 12 | <b>BOOST_PP_IIF</b>(<i>bit</i>, <i>t</i>, <i>f</i>) |
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| 13 | </div> |
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| 14 | <h4>Arguments</h4> |
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| 15 | <dl> |
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| 16 | <dt>bit</dt> |
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| 17 | <dd> |
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| 18 | The condition that determines if the result is <i>expr</i> or nothing. |
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| 19 | This value must expand to <i>0</i> or <i>1</i>. |
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| 20 | </dd> |
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| 21 | <dt>t</dt> |
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| 22 | <dd> |
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| 23 | The result of the expansion if <i>bit</i> is <i>1</i>. |
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| 24 | </dd> |
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| 25 | <dt>f</dt> |
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| 26 | <dd> |
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| 27 | The result of the expansion if <i>bit</i> is <i>0</i>. |
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| 28 | </dd> |
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| 29 | </dl> |
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| 30 | <h4>Remarks</h4> |
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| 31 | <div> |
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| 32 | This macro <i>does not</i> perform a boolean conversion on its first argument. |
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| 33 | If that conversion is necessary, use <b>BOOST_PP_IF</b> instead. |
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| 34 | </div> |
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| 35 | <h4>See Also</h4> |
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| 36 | <ul> |
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| 37 | <li><a href="if.html">BOOST_PP_IF</a></li> |
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| 38 | <li><a href="limit_mag.html">BOOST_PP_LIMIT_MAG</a></li> |
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| 39 | </ul> |
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| 40 | <h4>Requirements</h4> |
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| 41 | <div> |
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| 42 | <b>Header:</b> <a href="../headers/control/iif.html"><boost/preprocessor/control/iif.hpp></a> |
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| 43 | </div> |
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| 44 | <h4>Sample Code</h4> |
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| 45 | <div><pre> |
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| 46 | #include <<a href="../headers/control/iif.html">boost/preprocessor/control/iif.hpp</a>> |
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| 47 | #include <<a href="../headers/logical/or.html">boost/preprocessor/logical/or.hpp</a> |
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| 48 | |
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| 49 | #define OR_IF(p, q, t, f) <a href="iif.html">BOOST_PP_IIF</a>(<a href="or.html">BOOST_PP_OR</a>(p, q), t, f) |
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| 50 | |
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| 51 | OR_IF(1, 0, abc, xyz) // expands to abc |
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| 52 | OR_IF(0, 0, abc, xyz) // expands to xyz |
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| 53 | </pre></div> |
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| 54 | </body> |
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| 55 | </html> |
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