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<html><head><title>XLISP fourth</title>
<link rel="stylesheet" type="text/css" href="reference.css">
</head>
<body>
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<a href="reference-index.htm">Reference</a>
<hr>
<h1>fourth</h1>
<hr>
<p><table cellpadding="0" cellspacing="0" style="margin-left:10px"><tbody>
<tr valign="top">
<td><nobr>Type:</nobr></td>
<td><nobr> - </nobr></td>
<td width="100%"><nobr>function (subr)</nobr></td>
</tr>
<tr valign="top">
<td><nobr>Source:</nobr></td>
<td><nobr> - </nobr></td>
<td width="100%"><nobr>xlinit.c</nobr></td>
</tr>
</tbody></table></p>
<h2>Syntax</h2>
<dl>
<dt>(fourth <i>expr</i>)</dt>
<dd><i>expr</i> - a list or list expression<br>
returns - the fourth element of the list</dd>
</dl>
<h2>Description</h2>
<p>The 'fourth' function returns the fourth element of a list or list
expression. If the list is
<nobr><a href="nil.htm">NIL</a> ,</nobr>
<a href="nil.htm">NIL</a> is returned.</p>
<h2>Examples</h2>
<pre class="example">
(fourth '(1 2 3 4 5)) <font color="#008844">; returns 4</font>
(fourth NIL) <font color="#008844">; returns NIL</font>
(setq kids '(junie vickie cindy chris)) <font color="#008844">; set up variable KIDS</font>
(first kids) <font color="#008844">; returns JUNIE</font>
(second kids) <font color="#008844">; returns VICKIE</font>
(third kids) <font color="#008844">; returns CINDY</font>
(fourth kids) <font color="#008844">; returns CHRIS</font>
(rest kids) <font color="#008844">; returns (VICKIE CINDY CHRIS)</font>
</pre>
<p><b>Note:</b> This function is set to the same code as
<a href="caaaar.htm">cadddr</a>.</p>
<p>See the
<a href="../manual/xlisp-man-016.htm#fourth">fourth</a>
function in the <nobr>XLISP 2.0</nobr> manual.</p>
<p><nobr> <a href="#top">Back to Top</nobr></a></p>
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