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<html><head><title>XLISP :sescape</title>
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<h1>:sescape</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>keyword</nobr></td>
</tr>
<tr valign="top">
<td><nobr>Source:</nobr></td>
<td><nobr> - </nobr></td>
<td width="100%"><nobr>xlread.c</nobr></td>
</tr>
</tbody></table></p>
<h2>Syntax</h2>
<dl>
<dt> :sescape</dt>
</dl>
<h2>Description</h2>
<p>The ':sescape' keyword is an entry used in the
<a href="global-readtable.htm">*readtable*</a> system variable that contains
XLISP's data structures relating to the processing of characters from the
user [or files] and read-macro expansions. The existance of the ':sescape'
keyword means that the specified character is to be used as a single escape
character. The system defines that the the backslash character '\' is the
only defined ':sescape' character.</p>
<h2>Examples</h2>
<pre class="example">
<font color="#008844">;; define a function to look in a table</font>
<font color="#008844">;; and print out any :SESCAPE character</font>
(defun look-at (table)
(dotimes (ch 127)
(prog ((entry (aref table ch)))
(case entry
(:SESCAPE (princ (int-char ch)))
(t nil))))
(terpri))
(look-at *readtable*) <font color="#008844">; prints \</font>
</pre>
<p><b>Caution:</b> If you experiment with *readtable*, it is useful to save
the old value in a variable, so that you can restore the system state.</p>
<p>See the
<a href="../manual/xlisp-man-008.htm#sescape">:sescape</a>
keyword in the <nobr>XLISP 2.0</nobr> manual.</p>
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