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<title>BOOST_PP_TUPLE_ELEM</title>
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<div style="margin-left: 0px;">
The <b>BOOST_PP_TUPLE_ELEM</b> macro extracts an element from a <i>tuple</i>.
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<h4>Usage</h4>
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<b>BOOST_PP_TUPLE_ELEM</b>(<i>size</i>, <i>i</i>, <i>tuple</i>)
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<h4>Arguments</h4>
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<dt>size</dt>
<dd>
The size of the <i>tuple</i>.&nbsp;
Valid <i>tuple</i> sizes range from <i>0</i> to <b>BOOST_PP_LIMIT_TUPLE</b>.&nbsp;
</dd>
<dt>i</dt>
<dd>
The zero-based index into the <i>tuple</i> of the element to be extracted.&nbsp;
Valid values range from <i>0</i> to <i>size</i> - <i>1</i>.
</dd>
<dt>tuple</dt>
<dd>
The <i>tuple</i> from which an element is to be extracted.
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</dl>
<h4>Remarks</h4>
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The <i>size</i> argument must be the actual size of the <i>tuple</i>,
and <i>i</i> must be less than the size of the <i>tuple</i>.
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<h4>See Also</h4>
<ul>
<li><a href="limit_tuple.html">BOOST_PP_LIMIT_TUPLE</a></li>
</ul>
<h4>Requirements</h4>
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<b>Header:</b> &nbsp;<a href="../headers/tuple/elem.html">&lt;boost/preprocessor/tuple/elem.hpp&gt;</a>
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<h4>Sample Code</h4>
<div><pre>
#include &lt;<a href="../headers/tuple/elem.html">boost/preprocessor/tuple/elem.hpp</a>&gt;
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#define TUPLE (a, b, c, d)
<a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(4, 0, TUPLE) // expands to a
<a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(4, 3, TUPLE) // expands to d
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