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<html>
<head>
	<title>BOOST_PP_REPEAT_z</title>
	<link rel="stylesheet" type="text/css" href="../styles.css">
</head>
<body>
	<div style="margin-left:  0px;">
		The <b>BOOST_PP_REPEAT_<i>z</i></b> macro represents a reentry into the <b>BOOST_PP_REPEAT</b> repetition construct.
	</div>
	<h4>Usage</h4>
		<div class="code">
			<b>BOOST_PP_REPEAT_</b> ## <i>z</i>(<i>count</i>, <i>macro</i>, <i>data</i>)
		</div>
	<h4>Arguments</h4>
		<dl>
			<dt>z</dt>
			<dd>
				The next available <b>BOOST_PP_REPEAT</b> dimension.
			</dd>
			<dt>count</dt>
			<dd>
				The number of repetitious calls to <i>macro</i>.&nbsp;
				Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_REPEAT</b>.
			</dd>
			<dt>macro</dt>
			<dd>
				A ternary operation of the form <i>macro</i>(<i>z</i>, <i>n</i>, <i>data</i>).&nbsp;
				This macro is expanded by <b>BOOST_PP_REPEAT</b> with the next available repetition depth,
				the current repetition number, and the auxiliary <i>data</i> argument.&nbsp;
			</dd>
			<dt>data</dt>
			<dd>
				Auxiliary data passed to <i>macro</i>.
			</dd>
		</dl>
	<h4>Remarks</h4>
		<div>
			This macro expands to the sequence:
			<div>
				<i>macro</i>(<i>z</i>, <i>0</i>, <i>data</i>) <i>macro</i>(<i>z</i>, <i>1</i>, <i>data</i>) ... <i>macro</i>(<i>z</i>, <i>count</i> - <i>1</i>, <i>data</i>)
			</div>
		</div>
		<div>
			At certain times, it may be necessary to perform the concatenation with <b>BOOST_PP_CAT</b> rather than the preprocessor token-pasting operator.&nbsp;
			This happens when the <i>z</i> value is a macro invocation itself.&nbsp;
			It needs a delay to allow it to expand.&nbsp;
			The syntax in such a scenario becomes:
			<div>
				<b>BOOST_PP_CAT</b>(<b>BOOST_PP_REPEAT_</b>, <i>z</i>)(<i>count</i>, <i>macro</i>, <i>data</i>)
			</div>
		</div>
	<h4>See Also</h4>
		<ul>
			<li><a href="cat.html">BOOST_PP_CAT</a></li>
			<li><a href="limit_repeat.html">BOOST_PP_LIMIT_REPEAT</a></li>
			<li><a href="repeat.html">BOOST_PP_REPEAT</a></li>
		</ul>
	<h4>Requirements</h4>
		<div>
			<b>Header:</b> &nbsp;<a href="../headers/repetition/repeat.html">&lt;boost/preprocessor/repetition/repeat.hpp&gt;</a>
		</div>
	<h4>Sample Code</h4>
<div><pre>
#include &lt;<a href="../headers/arithmetic/inc.html">boost/preprocessor/arithmetic/inc.hpp</a>&gt;
#include &lt;<a href="../headers/punctuation/comma_if.html">boost/preprocessor/punctuation/comma_if.hpp</a>&gt;
#include &lt;<a href="../headers/repetition/repeat.html">boost/preprocessor/repetition/repeat.hpp</a>&gt;

#define TEXT(z, n, text) <a href="comma_if.html">BOOST_PP_COMMA_IF</a>(n) text

#define TEMPLATE(z, n, _) \
   <a href="comma_if.html">BOOST_PP_COMMA_IF</a>(n) \
   template&lt; \
      <a href="repeat_z.html">BOOST_PP_REPEAT_</a> ## z( \
         <a href="inc.html">BOOST_PP_INC</a>(n), \
         TEXT, class \
      ) \
   &gt; class T ## n \
   /**/

<a href="repeat.html">BOOST_PP_REPEAT</a>(3, TEMPLATE, nil)
   /*
   expands to:
      template&lt;class&gt; class T0,
      template&lt;class, class&gt; class T1,
      template&lt;class, class, class&gt; class T2
   */
</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>