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<RefEntry id="match-split">
<!-- This file is generated automatically from the DSSSL source. -->
<!-- Do not edit this file! -->
<?html-filename match-split.html>
<RefMeta>
<RefEntryTitle>match-split</RefEntryTitle>
<RefMiscInfo Role="file">dblib.dsl</RefMiscInfo>
</RefMeta>
<RefNameDiv>
<RefName>match-split</RefName>
<RefPurpose>Splits string at target and returns the resulting list of tokens</RefPurpose>
</RefNameDiv>
<RefSynopsisDiv><Title>Synopsis</Title>
<Synopsis>
(match-split string target)
</Synopsis>
</RefSynopsisDiv>
<RefSect1><Title>Description</Title>
<para>
Splits string at every occurance of target and returns the result
as a list. Note that <literal>match-split</literal> returns the occurances of <literal>target</literal>
in the list of tokens.
</para>
<variablelist>
<varlistentry><term><literal>string</literal></term>
<listitem>
<para>
The string to split.
</para>
</listitem>
</varlistentry>
<varlistentry><term><literal>target</literal></term>
<listitem>
<para>
The string which is a delimiter between tokens
</para>
</listitem>
</varlistentry>
</variablelist>
</RefSect1>
<RefSect1><Title>Example</Title>
<para>
<literal>"this is a test"</literal> split at <literal>"is"</literal> returns
<literal>("th" "is" " " "is" " a test")</literal>
</para>
</RefSect1>
<RefSect1><Title>Author</Title>
<para>
Norman Walsh, <ndw@nwalsh.com>
</para>
</RefSect1>
<RefSect1><Title>Source Code</Title>
<ProgramListing>
(define (match-split string target)
;; Splits string at target and returns the resulting list of tokens
(if (string? string)
(let loop ((result '()) (current "") (rest string))
(if (< (string-length rest) (string-length target))
(append result (if (equal? (string-append current rest) "")
'()
(list (string-append current rest))))
(if (equal? target (substring rest 0 (string-length target)))
(loop (append result
(if (equal? current "")
'()
(list current))
(list target))
""
(substring rest (string-length target)
(string-length rest)))
(loop result
(string-append current (substring rest 0 1))
(substring rest 1 (string-length rest))))))
(list string)))
</ProgramListing>
</RefSect1>
</RefEntry>
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