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<title>BOOST_PP_LIST_FOLD_RIGHT_2ND</title>
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The <b>BOOST_PP_LIST_FOLD_RIGHT_2ND</b> macro folds (or accumulates) the elements of a <i>list</i> right-to-left.
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<h4>Usage</h4>
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<b>BOOST_PP_LIST_FOLD_RIGHT_2ND</b>(<i>op</i>, <i>state</i>, <i>list</i>)
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<h4>Arguments</h4>
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<dt>op</dt>
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A ternary operation of the form <i>op</i>(<i>d</i>, <i>state</i>, <i>elem</i>).&nbsp;
This macro is called for each element in <i>list</i>--each time returning a new <i>state</i>.&nbsp;
This operation is expanded by <b>BOOST_PP_LIST_FOLD_RIGHT</b> with the next available <b>BOOST_PP_WHILE</b> iteration,
the current <i>state</i>, and the current element.
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<dt>state</dt>
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The initial state of the fold.
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<dt>list</dt>
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The <i>list</i> to be folded.
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<h4>Remarks</h4>
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This macro does not have the same signature as it previously did.&nbsp;
The arguments have been swapped to provide a uniform interface with <b>BOOST_PP_LIST_FOLD_LEFT</b>.
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For the <i>list</i>, (<i>0</i>, (<i>1</i>, (<i>2</i>, <b>BOOST_PP_NIL</b>))), this macro expands to:
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<i>op</i>(<i>d</i>, <i>op</i>(<i>d</i>, <i>op</i>(<i>d</i>, <i>state</i>, <i>0</i>), <i>1</i>), <i>2</i>)
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This macro is deprecated.&nbsp;
Use <b>BOOST_PP_LIST_FOLD_RIGHT_<i>d</i></b> instead.
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<h4>See Also</h4>
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<li><a href="list_fold_right.html">BOOST_PP_LIST_FOLD_RIGHT</a></li>
<li><a href="list_fold_right_d.html">BOOST_PP_LIST_FOLD_RIGHT_<i>d</i></a></li>
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<h4>Requirements</h4>
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<b>Header:</b> &nbsp;<a href="../headers/list/fold_right.html">&lt;boost/preprocessor/list/fold_right.hpp&gt;</a>
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<h4>Sample Code</h4>
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#include &lt;<a href="../headers/cat.html">boost/preprocessor/cat.hpp</a>&gt;
#include &lt;<a href="../headers/list/fold_right.html">boost/preprocessor/list/fold_right.hpp</a>&gt;
#define LIST (a, (b, (c, <a href="nil.html">BOOST_PP_NIL</a>)))
#define OP(d, state, x) <a href="cat.html">BOOST_PP_CAT</a>(state, x)
<a href="list_fold_right_2nd.html">BOOST_PP_LIST_FOLD_RIGHT_2ND</a>(OP, _, LIST) // expands to _cba
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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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