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	<title>BOOST_PP_COMMA_IF</title>
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	<div style="margin-left:  0px;">
		The <b>BOOST_PP_COMMA_IF</b> macro conditionally expands to a comma.
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	<h4>Usage</h4>
		<div class="code">
			<b>BOOST_PP_COMMA_IF</b>(<i>cond</i>)
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	<h4>Arguments</h4>
		<dl>
			<dt>cond</dt>
			<dd>
				The condition that determines if a the macro expands to a comma or nothing.&nbsp;
				Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
			</dd>
		</dl>
	<h4>Remarks</h4>
		<div>
			If <i>cond</i> expands to <i>0</i>, this macro expands to nothing.&nbsp;
			Otherwise, it expands to a comma.
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		<div>
			The preprocessor interprets commas as argument separators in macro invocations.&nbsp;
			Because of this, commas require special handling.
		</div>
	<h4>See Also</h4>
		<ul>
			<li><a href="limit_mag.html">BOOST_PP_LIMIT_MAG</a></li>
		</ul>
	<h4>Requirements</h4>
		<div>
			<b>Header:</b> &nbsp;<a href="../headers/punctuation/comma_if.html">&lt;boost/preprocessor/punctuation/comma_if.hpp&gt;</a>
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	<h4>Sample Code</h4>
<div><pre>
#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 MACRO(z, n, text) <a href="comma_if.html">BOOST_PP_COMMA_IF</a>(n) text

<a href="repeat.html">BOOST_PP_REPEAT</a>(3, MACRO, class) // expands to class, class, class
</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>
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