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+<html><head><title>XLISP *unbound*</title>
+
+<link rel="stylesheet" type="text/css" href="reference.css">
+
+</head>
+
+<body>
+
+<a href="../start.htm">Nyquist / XLISP 2.0</a>&nbsp; -&nbsp;
+<a href="../manual/contents.htm">Contents</a> |
+<a href="../tutorials/tutorials.htm">Tutorials</a> |
+<a href="../examples/examples.htm">Examples</a> |
+<a href="reference-index.htm">Reference</a>
+
+<hr>
+
+<h1>*unbound*</h1>
+
+<hr>
+
+<p><table cellpadding="0" cellspacing="0" style="margin-left:10px"><tbody>
+<tr valign="top">
+  <td><nobr>Type:</nobr></td>
+  <td><nobr>&nbsp;&nbsp;-&nbsp;&nbsp;</nobr></td>
+  <td width="100%"><nobr>system constant</nobr></td>
+</tr>
+<tr valign="top">
+  <td><nobr>Source:</nobr></td>
+  <td><nobr>&nbsp;&nbsp;-&nbsp;&nbsp;</nobr></td>
+  <td width="100%"><nobr>xlinit.c, xlsym.c</nobr></td>
+</tr>
+</tbody></table></p>
+
+<h2>Syntax</h2>
+
+<dl>
+<dt>&nbsp;*unbound*</dt>
+</dl>
+
+<h2>Description</h2>
+
+<p>The *unbound* system constant is used to indicate when a symbol has no
+value. *unbound* is set to the value *unbound*. This means that the system
+thinks the symbol *unbound* has no value.</p>
+
+<h2>Examples</h2>
+
+<pre class="example">
+*unbound*            <font color="#008844">; error: unbound variable</font>
+(setq a 5)           <font color="#008844">; returns 5</font>
+a                    <font color="#008844">; returns 5</font>
+(setq a '*unbound*)  <font color="#008844">; returns *UNBOUND*</font>
+a                    <font color="#008844">; error: unbound variable</font>
+</pre>
+
+<p>See the
+<a href="../manual/xlisp-man-011.htm#unbound">*unbound*</a>
+system constant in the <nobr>XLISP 2.0</nobr> manual.</p>
+
+<p><nobr>&nbsp;&nbsp;<a href="#top">Back to Top</nobr></a></p>
+
+<hr>
+
+<a href="../start.htm">Nyquist / XLISP 2.0</a>&nbsp; -&nbsp;
+<a href="../manual/contents.htm">Contents</a> |
+<a href="../tutorials/tutorials.htm">Tutorials</a> |
+<a href="../examples/examples.htm">Examples</a> |
+<a href="reference-index.htm">Reference</a>
+
+</body></html>
+\ No newline at end of file