libs/preprocessor/doc/ref/intercept.html


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<html>
<head>
	<title>BOOST_PP_INTERCEPT</title>
	<link rel="stylesheet" type="text/css" href="../styles.css">
</head>
<body>
	<div style="margin-left:  0px;">
		The <b>BOOST_PP_INTERCEPT</b> macro intercepts a numeric concatenation and expands to nothing.
	</div>
	<h4>Usage</h4>
		<div class="code">
			<b>BOOST_PP_INTERCEPT</b>
		</div>
	<h4>Remarks</h4>
		<div>
			This macro is used to intercept concatenations performed by various other library constructs.&nbsp;
			It is typically used after other text to prevent eat the concatenation expand to nothing.&nbsp;
			This macro can only intercept integer constants in the range of <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
		</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/facilities/intercept.html">&lt;boost/preprocessor/facilities/intercept.hpp&gt;</a>
		</div>
	<h4>Sample Code</h4>
<div><pre>
#include &lt;<a href="../headers/facilities/intercept.html">boost/preprocessor/facilities/intercept.hpp</a>&gt;
#include &lt;<a href="../headers/repetition/enum_binary_params.html">boost/preprocessor/repetition/enum_binary_params.hpp</a>&gt;

<a href="enum_binary_params.html">BOOST_PP_ENUM_BINARY_PARAMS</a>(3, class T, = U)
// expands to class T0 = U0, class T1 = U1, class T2 = U2

<a href="enum_binary_params.html">BOOST_PP_ENUM_BINARY_PARAMS</a>(3, class T, = int <a href="intercept.html">BOOST_PP_INTERCEPT</a>)
// expands to class T0 = int, class T1 = int, class T2 = int
</pre></div>
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		<i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
		</br><i>© Copyright Paul Mensonides 2002</i>
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	<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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