Re: [xsl] Retrieving sequence of unique strings from another sequence

["G. Ken Holman" <gkholman@xxxxxxxxxxxxxxxxxxxx>]

At 2010-01-05 13:41 -0500, Houghton,Andrew wrote:
> I have a sequence of strings, e.g., ('abc', 'def', 'def', 'ghi'), 
> and I want to create a new sequence that will have only the unique 
> strings in it.  The XSL 2.0 function distinct-values is not what I 
> want because:
>
>   <xsl:variable name="list" as="xsd:string*" select="('abc', 'def', 
> 'def', 'ghi')" />
>   <xsl:variable name="uniq" as="xsd:string*" 
> select="distinct-values($list)" />
>
> will result in a sequence of ('abc', 'def', 'ghi') which is not what 
> I'm looking for.  What I am looking for is the sequence ('abc', 
> 'ghi').  Unix people will recognize that distinct-values() returns 
> the result of the uniq command without any options.  While what I'm 
> looking for is the result of the uniq command with the -u option.
>
> Can anyone suggest how I might use one or more XSL 2.0 functions to 
> return only the unique strings.

I hope the solution below helps.

. . . . . . .  Ken

T:\ftemp>xslt2 andy.xsl andy.xsl
abc ghi
T:\ftemp>type andy.xsl
<?xml version="1.0" encoding="US-ASCII"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
                xmlns:xsd="http://www.w3.org/2001/XMLSchema";
                version="2.0">

<xsl:output method="text"/>

<xsl:template match="/">
  <xsl:variable name="list" as="xsd:string*"
                select="('abc', 'def', 'def', 'ghi')"/>
  <xsl:variable name="uniq" as="xsd:string*"
                select="for $each in $list return
                        if( count($list[.=$each])=1 ) then $each else ()"/>
  <xsl:value-of select="$uniq"/>
</xsl:template>

</xsl:stylesheet>
T:\ftemp>


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