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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>).
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>.
</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>.
It builds a new <i>list</i> out of the results of each call.
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>.
There is no longer any such restriction.
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> <a href="../headers/list/transform.html"><boost/preprocessor/list/transform.hpp></a>
</div>
<h4>Sample Code</h4>
<div><pre>
#include <<a href="../headers/arithmetic/dec.html">boost/preprocessor/arithmetic/dec.hpp</a>>
#include <<a href="../headers/list/transform.html">boost/preprocessor/list/transform.hpp</a>>
#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>
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