preprocessor/doc/ref/list_transform.html

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<head>
	<title>BOOST_PP_LIST_TRANSFORM</title>
	<link rel="stylesheet" type="text/css" href="../styles.css">
</head>
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	<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>
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</html>
lib cleanup [SVN r15693] 2002-10-03 22:13:37 +00:00			`<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>`
headers/xxx.hpp.html >> headers/xxx.html [SVN r25656] 2004-10-11 06:58:45 +00:00			`<b>Header:</b>  <a href="../headers/list/transform.html"><boost/preprocessor/list/transform.hpp></a>`
lib cleanup [SVN r15693] 2002-10-03 22:13:37 +00:00			`</div>`
			`<h4>Sample Code</h4>`
			`<div><pre>`
headers/xxx.hpp.html >> headers/xxx.html [SVN r25656] 2004-10-11 06:58:45 +00:00			`#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>>`
lib cleanup [SVN r15693] 2002-10-03 22:13:37 +00:00
			`#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>`
			`</body>`
			`</html>`