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<title>BOOST_PP_SEQ_FOLD_RIGHT</title>
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The <b>BOOST_PP_SEQ_FOLD_RIGHT</b> macro folds (or accumulates) the elements of
a <i>seq</i> right-to-left.
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Usage
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<b>BOOST_PP_SEQ_FOLD_RIGHT</b>(<i>op</i>, <i>state</i>, <i>seq</i>)
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Arguments
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<dt>op</dt>
<dd>
A ternary operation of the form <i>op</i>(<i>s</i>, <i>state</i>, <i>elem</i>).&nbsp;
This macro is called for each element in <i>seq</i>--each time returning a new <i>state</i>.&nbsp;
This operation is expanded by <b>BOOST_PP_SEQ_FOLD_RIGHT</b> with the next
available fold step, the current <i>state</i>, and the current element.
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<dt>state</dt>
<dd>
The initial state of the fold.
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<dt>seq</dt>
<dd>
The <i>seq</i> to be folded.
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<h4>
Remarks
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For the <i>seq</i>, (<i>0</i>)(<i>1</i>)(<i>2</i>), this macro expands to:
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<i>op</i>(<i>s</i>, <i>op</i>(<i>s</i>, <i>op</i>(<i>s</i>, <i>state</i>, <i>2</i>),
<i>1</i>), <i>0</i>)
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For maximum efficiency, <b>BOOST_PP_SEQ_FOLD_RIGHT</b> can be reentered with <b>BOOST_PP_SEQ_FOLD_RIGHT_<i>s</i></b>.
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See Also
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<ul>
<li>
<a href="seq_fold_right_s.html">BOOST_PP_SEQ_FOLD_RIGHT_<i>s</i></a></li>
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Requirements
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<b>Header:</b> &nbsp;<a href="../headers/seq/fold_right.html">&lt;boost/preprocessor/seq/fold_right.hpp&gt;</a>
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Sample Code
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<pre>
#include &lt;<a href="../headers/cat.html">boost/preprocessor/cat.hpp</a>&gt;
#include &lt;<a href="../headers/seq/elem.html">boost/preprocessor/seq/elem.hpp</a>&gt;
#include &lt;<a href="../headers/seq/fold_right.html">boost/preprocessor/seq/fold_right.hpp</a>&gt;
#include &lt;<a href="../headers/seq/pop_back.html">boost/preprocessor/seq/pop_back.hpp</a>&gt;
#define SEQ (t)(s)(o)(o)(b)
#define OP(s, state, x) <a href="cat.html">BOOST_PP_CAT</a>(state, x)
<a href="seq_fold_right.html">BOOST_PP_SEQ_FOLD_RIGHT</a>(OP, <a href="seq_elem.html">BOOST_PP_SEQ_ELEM</a>(4, SEQ), <a href="seq_pop_back.html">BOOST_PP_SEQ_POP_BACK</a>(SEQ)) // expands to boost
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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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