49 lines
1.9 KiB
HTML
49 lines
1.9 KiB
HTML
<html>
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<head>
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<title>BOOST_PP_DEDUCE_R</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;">
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The <b>BOOST_PP_DEDUCE_R</b> macro manually deduces the state of the <b>BOOST_PP_FOR</b> construct.
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</div>
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<h4>Usage</h4>
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<div class="code">
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<b>BOOST_PP_DEDUCE_R</b>()
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</div>
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<h4>Remarks</h4>
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<div>
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This macro is intended to avoid the use of <i>automatic-recursion</i> at deep expansion depths.
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<i>Automatic-recursion</i> at such depths can be inefficient on some preprocessors.
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It is not intended to be used directly with the invocation of macros with a <b>_R</b> suffix such as:
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<div>
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<b>BOOST_PP_LIST_ENUM_R</b>(<b>BOOST_PP_DEDUCE_R</b>(), (a, (b, (c, <b>BOOST_PP_NIL</b>))))
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</div>
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If it is used in this context, the <b>_R</b> macro will fail.
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The <b>_R</b> macros directly concatenate to the <i>r</i> parameter that is passed to them,
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which would prevent <b>BOOST_PP_DEDUCE_R</b>() from expanding.
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Furthermore, it is pointless to use this macro in a situation such as this
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because it would already be too late to gain any efficiency.
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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="for.html">BOOST_PP_FOR</a></li>
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</ul>
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<h4>Requirements</h4>
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<div>
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<b>Header:</b> <a href="../headers/repetition/deduce_r.html"><boost/preprocessor/repetition/deduce_r.hpp></a>
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</div>
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<hr size="1">
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<div style="margin-left: 0px;">
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<i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
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</br><i>© Copyright Paul Mensonides 2002</i>
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</div>
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<div style="margin-left: 0px;">
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<p><small>Distributed under the Boost Software License, Version 1.0. (See
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accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
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copy at <a href=
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"http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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</div>
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</body>
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</html>
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