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<html>
<head>
	<title>BOOST_PP_LIST_TRANSFORM</title>
	<link rel="stylesheet" type="text/css" href="../styles.css">
</head>
<body>
	<div style="margin-left:  0px;">
		The <b>BOOST_PP_LIST_TRANSFORM</b> macro transforms each element in a <i>list</i> according to a supplied transformation.
	</div>
	<h4>Usage</h4>
		<div class="code">
			<b>BOOST_PP_LIST_TRANSFORM</b>(<i>op</i>, <i>data</i>, <i>list</i>)
		</div>
	<h4>Arguments</h4>
		<dl>
			<dt>op</dt>
			<dd>
				A ternary predicate of the form <i>op</i>(<i>d</i>, <i>data</i>, <i>elem</i>).&nbsp;
				This transformation is expanded by <b>BOOST_PP_LIST_TRANSFORM</b> for each element in <i>list</i> with the next available <b>BOOST_PP_WHILE</b> iteration,
				the auxiliary <i>data</i>, and the current element in <i>list</i>.&nbsp;
			</dd>
			<dt>data</dt>
			<dd>
				Auxiliary data passed to <i>pred</i>.
			</dd>
			<dt>list</dt>
			<dd>
				The <i>list</i> to be transformed.
			</dd>
		</dl>
	<h4>Remarks</h4>
		<div>
			This macro expands <i>op</i> for each element in <i>list</i>.&nbsp;
			It builds a new <i>list</i> out of the results of each call.&nbsp;
			If, for example, <i>list</i> is (<i>a</i>, (<i>b</i>, (<i>c</i>, <b>BOOST_PP_NIL</b>))),
			this macro expands to...
			<div>
				(<i>op</i>(<i>d</i>, <i>data</i>, <i>a</i>), (<i>op</i>(<i>d</i>, <i>data</i>, <i>b</i>), (<i>op</i>(<i>d</i>, <i>data</i>, <i>c</i>), <b>BOOST_PP_NIL</b>)))
			</div>
		</div>
		<div>
			Previously, this macro could not be used inside <b>BOOST_PP_WHILE</b>.&nbsp;
			There is no longer any such restriction.&nbsp;
			It is more efficient, however, to use <b>BOOST_PP_LIST_TRANSFORM_D</b> in such a situation.
		</div>
	<h4>See Also</h4>
		<ul>
			<li><a href="list_transform_d.html">BOOST_PP_LIST_TRANSFORM_D</a></li>
		</ul>
	<h4>Requirements</h4>
		<div>
			<b>Header:</b> &nbsp;<a href="../headers/list/transform.html">&lt;boost/preprocessor/list/transform.hpp&gt;</a>
		</div>
	<h4>Sample Code</h4>
<div><pre>
#include &lt;<a href="../headers/arithmetic/dec.html">boost/preprocessor/arithmetic/dec.hpp</a>&gt;
#include &lt;<a href="../headers/list/transform.html">boost/preprocessor/list/transform.hpp</a>&gt;

#define LIST (1, (3, (2, (5, <a href="nil.html">BOOST_PP_NIL</a>))))

#define OP(d, data, elem) <a href="dec.html">BOOST_PP_DEC</a>(elem)

<a href="list_transform.html">BOOST_PP_LIST_TRANSFORM</a>(OP, 3, LIST)
   // expands to (0, (2, (1, (4, <a href="nil.html">BOOST_PP_NIL</a>))))
</pre></div>
	<hr size="1">
	<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>
</body>
</html>