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	<title>BOOST_PP_LIST_FOLD_LEFT_d</title>
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	<div style="margin-left:  0px;">
		The <b>BOOST_PP_LIST_FOLD_LEFT_<i>d</i></b> macro folds (or accumulates) the elements of a <i>list</i> left-to-right.&nbsp;
		It reenters <b>BOOST_PP_WHILE</b> with maximum efficiency.
	</div>
	<h4>Usage</h4>
		<div class="code">
			<b>BOOST_PP_LIST_FOLD_LEFT_</b> ## <i>d</i>(<i>op</i>, <i>state</i>, <i>list</i>)
		</div>
	<h4>Arguments</h4>
		<dl>
			<dt>d</dt>
			<dd>
				The next available <b>BOOST_PP_WHILE</b> iteration.
			</dd>
			<dt>op</dt>
			<dd>
				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_LEFT</b> with the next available <b>BOOST_PP_WHILE</b> iteration,
				the current <i>state</i>, and the current element.
			</dd>
			<dt>state</dt>
			<dd>
				The initial state of the fold.
			</dd>
			<dt>list</dt>
			<dd>
				The <i>list</i> to be folded.
			</dd>
		</dl>
	<h4>Remarks</h4>
		<div>
			For the <i>list</i>, (<i>0</i>, (<i>1</i>, (<i>2</i>, <b>BOOST_PP_NIL</b>))), this macro expands to:
			<div>
				<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>)
			</div>
		</div>
	<h4>See Also</h4>
		<ul>
			<li><a href="list_fold_left.html">BOOST_PP_LIST_FOLD_LEFT</a></li>
		</ul>
	<h4>Requirements</h4>
		<div>
			<b>Header:</b> &nbsp;<a href="../headers/list/fold_left.html">&lt;boost/preprocessor/list/fold_left.hpp&gt;</a>
		</div>
	<h4>Sample Code</h4>
<div><pre>
#include &lt;<a href="../headers/cat.html">boost/preprocessor/cat.hpp</a>&gt;
#include &lt;<a href="../headers/list/fold_left.html">boost/preprocessor/list/fold_left.hpp</a>&gt;

#define L1 (a, (b, (c, <a href="nil.html">BOOST_PP_NIL</a>)))
#define L2 (L1, (L1, (L1, <a href="nil.html">BOOST_PP_NIL</a>)))

#define OP(d, state, x) (<a href="list_fold_left_d.html">BOOST_PP_LIST_FOLD_LEFT_</a> ## d(OP_2, _, x), state)
#define OP_2(d, state, x) <a href="cat.html">BOOST_PP_CAT</a>(state, x)

<a href="list_fold_left.html">BOOST_PP_LIST_FOLD_LEFT</a>(OP, <a href="nil.html">BOOST_PP_NIL</a>, L2)
/*
   expands to:
   (_abc, (_abc, (_abc, <a href="nil.html">BOOST_PP_NIL</a>)))
*/
</pre></div>
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	<div style="margin-left: 0px;">
		<i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
		</br><i>© Copyright Paul Mensonides 2002</i>
	</div>
	<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>
	</div>
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