<RefEntry id="strip">
<!-- This file is generated automatically from the DSSSL source. -->
<!-- Do not edit this file! -->
<?html-filename strip.html>

<RefMeta>
  <RefEntryTitle>strip</RefEntryTitle>
  <RefMiscInfo Role="file">dblib.dsl</RefMiscInfo>
</RefMeta>

<RefNameDiv>
  <RefName>strip</RefName>
  <RefPurpose>Strip leading and trailing characters off of a string</RefPurpose>
</RefNameDiv>

<RefSynopsisDiv><Title>Synopsis</Title>
<Synopsis>
(strip str #!optional (stripchars '(#\space #\&#RE #\U-0009)))
</Synopsis>
</RefSynopsisDiv>

<RefSect1><Title>Description</Title>

<para>
Strips leading and trailing characters in the <literal>stripchars</literal> list
off of a string and returns the stripped string.
</para>
<variablelist>
<varlistentry><term><literal>str</literal></term>
<listitem>
<para>
The string to strip
</para>
</listitem>
</varlistentry>
<varlistentry><term><literal>stripchars</literal></term>
<listitem>
<para>
A list of characters that should
be stripped.
</para>
</listitem>
</varlistentry>
</variablelist>

</RefSect1>

<RefSect1><Title>Author</Title>

<para>
Norman Walsh, &lt;ndw@nwalsh.com&gt;
</para>
</RefSect1>
<RefSect1><Title>Source Code</Title>

<ProgramListing>
(define (strip str #!optional (stripchars '(#\space #\&#RE #\U-0009)))
  ;; Strip leading and trailing characters off of a string
  (let* ((startpos (let loop ((count 0))
		     (if (>= count (string-length str))
			 (string-length str)
			 (if (member (string-ref str count) stripchars)
			     (loop (+ count 1))
			     count))))
	 (tailstr  (substring str startpos (string-length str)))
	 (endpos   (let loop ((count (- (string-length tailstr) 1)))
		     (if (< count 1)
			 0
			 (if (member (string-ref tailstr count) stripchars)
			     (loop (- count 1))
			     count)))))
    (if (or (< endpos 0)
	    (string=? tailstr ""))
	""
	(substring tailstr 0 (+ endpos 1)))))
</ProgramListing>
</RefSect1>

</RefEntry>