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+<html>
+<head>
+	<title>BOOST_PP_EXPAND</title>
+	<link rel="stylesheet" type="text/css" href="../styles.css">
+	<script language="javascript" type="text/javascript" src="../scripts.js"></script>
+</head>
+<body onload="init('sample');">
+	<div style="margin-left:  0px;">
+		The <b>BOOST_PP_EXPAND</b> macro performs a double macro-expansion on its argument.
+	</div>
+	<h4>Usage</h4>
+		<div class="code">
+			<b>BOOST_PP_EXPAND</b>(<i>x</i>)
+		</div>
+	<h4>Arguments</h4>
+		<dl>
+			<dt>x</dt>
+			<dd>
+				The argument to be expanded twice.
+			</dd>
+		</dl>
+	<h4>Remarks</h4>
+		<div>
+			This macro is useful when a delay is necessary to produce the correct semantics of a macro invocation.&nbsp;
+			For example, when a macro expands to an argument list to another macro.&nbsp;
+			This macro will expand the the argument list on the first pass, and then rescan to expand any more macros.
+		</div>
+	<h4>Requirements</h4>
+		<div>
+			<b>Header:</b> &nbsp;<a href="../headers/facilities/expand.hpp.html">&lt;boost/preprocessor/facilities/expand.hpp&gt;</a>
+		</div>
+	<h4><a class="local" onclick="toggle('sample');" onmouseover="change(this);" onmouseout="revert(this);">Sample Code</a></h4>
+<div id="sample"><pre>
+#include &lt;boost/preprocessor/control/if.hpp&gt;
+#include &lt;boost/preprocessor/facilities/expand.hpp&gt;
+
+#define MACRO(a, b, c) (a)(b)(c)
+#define ARGS() (1, 2, 3)
+
+BOOST_PP_EXPAND(MACRO ARGS) // expands to (1)(2)(3)
+
+#define SAMPLE(n) /* ... */ \
+   BOOST_PP_EXPAND(         \
+      MACRO,                \
+      BOOST_PP_IF(          \
+         n,                 \
+         (x, y, z),         \
+         (a, b, c)          \
+      )                     \
+   )                        \
+   /**/
+
+SAMPLE(0) // expands to (a)(b)(c)
+SAMPLE(1) // expands to (x)(y)(z)
+<pre></div>
+</body>
+</html>