2002-10-03 22:13:37 +00:00
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<head>
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<title>BOOST_PP_LIST_IS_NIL</title>
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<link rel="stylesheet" type="text/css" href="../styles.css">
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</head>
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<body>
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<div style="margin-left: 0px;">
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The <b>BOOST_PP_LIST_IS_NIL</b> macro is a predicate that determines if a <i>list</i> is nil.
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</div>
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<h4>Usage</h4>
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<div class="code">
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<b>BOOST_PP_LIST_IS_NIL</b>(<i>list</i>)
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</div>
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<h4>Arguments</h4>
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<dl>
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<dt>list</dt>
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<dd>
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A <i>list</i>.
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</dd>
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</dl>
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<h4>Remarks</h4>
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<div>
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If <i>list</i> is nil, this macro expands to <i>1</i>.
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Otherwise, it expands to <i>0</i>.
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</div>
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<h4>Requirements</h4>
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<div>
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2004-10-11 06:58:45 +00:00
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<b>Header:</b> <a href="../headers/list/adt.html"><boost/preprocessor/list/adt.hpp></a>
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2002-10-03 22:13:37 +00:00
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</div>
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<h4>Sample Code</h4>
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<div><pre>
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2004-10-11 06:58:45 +00:00
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#include <<a href="../headers/list/adt.html">boost/preprocessor/list/adt.hpp</a>>
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2002-10-03 22:13:37 +00:00
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#define LIST (a, <a href="nil.html">BOOST_PP_NIL</a>)
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<a href="list_is_nil.html">BOOST_PP_LIST_IS_NIL</a>(LIST) // expands to 0
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<a href="list_is_nil.html">BOOST_PP_LIST_IS_NIL</a>(<a href="list_rest.html">BOOST_PP_LIST_REST</a>(LIST)) // expands to 1
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</pre></div>
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</body>
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</html>
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