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<html><head><title>XLISP tring-equal</title>
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<h1>string-equal</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>xlstr.c</nobr></td>
</tr>
</tbody></table></p>
<h2>Syntax</h2>
<dl>
<dt>(string-equal <i>string1 string2</i> [<i>key offset</i>] ... )</dt>
<dd><i>stringN</i> - a string expression<br>
<i>key</i> - a keyword [one of :start1 :start2 :end1 :end2]<br>
<i>offset</i> - an optional integer expression for a keyword<br>
returns - <a href="t.htm"> T </a> if <i>string1</i>
equal to <i>string2</i>,
<a href="nil.htm">NIL</a> otherwise<br>
<b>Note:</b> case is not significant with this function</dd>
</dl>
<h2>Description</h2>
<p>The 'string-equal' function takes two string arguments. It checks to see
if the string arguments have the same values.
<a href="t.htm"> T </a> is returned if 'string1' is
equal to 'string2', <a href="nil.htm">NIL</a> is returned
otherwise. This test is not case sensitive, the character '#\a' is
considered to be the same as '#\A'.</p>
<p>The keyword arguments allow for accessing substrings within 'string1' and
'string2'. The keyword arguments each require a keyword ':start1', ':end1',
':start2' or ':end2' and a single integer expression as a pair with the
keyword first and the integer second. The pairs may be in any order. The
':startN' keywords specify the starting offset of the substring. A value of
0 starts the string at the beginning [no offset]. The ':endN' keywords
specify the ending offset of the substring. A value of 3 ends the string
after the 3rd character [an offset of 3 characters].</p>
<h2>Examples</h2>
<pre class="example">
(string-equal "a" "b") <font color="#008844">; returns NIL</font>
(string-equal "a" "a") <font color="#008844">; returns T</font>
(string-equal "a" "A") <font color="#008844">; returns T</font>
(string-equal "A" "a") <font color="#008844">; returns T</font>
(string-equal "abc" "abc ") <font color="#008844">; returns NIL</font>
(string-equal "J Smith" "K Smith" :start1 1 :start2 1) <font color="#008844">; strip off the first chars</font>
<font color="#008844">; returns T</font>
(string-equal "abc" "123456789" :end2 3 :end1 3) <font color="#008844">; leave just the first 3 chars</font>
<font color="#008844">; returns NIL</font>
</pre>
<p><b>Bug:</b> The 'string-equal' function is listed in the original XLISP
documentation as 'string-equalp'. In the XLISP interpreter a call to
'string-equalp' causes an error:</p>
<pre class="example">
<font color="#AA0000">error: unbound function - STRING-EQUALP</font>
</pre>
<p>The 'string-equal' function works exactly as the 'string-equalp' function
described in the XLISP manual. This bug had obviously been corrected in
the manual only but never in the interpreter. As the bug still exists with
<nobr>Nyquist 2.36</nobr> in <nobr>July 2007</nobr> as well as all other
<nobr>XLISP 2.x</nobr> implementations I know, I have changed both manuals
to 'string-equal' even if I myself whould consider 'string-equalp' as the
better name.</p>
<p>See the
<a href="../manual/xlisp-man-025.htm#string-equalp">string-equal</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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