Re: Exclude by Sibling Condition

On Thu, 1 Dec 2005 20:07:27 -0600
"Jay Bryant" <jay@xxxxxxxxxxxx> wrote:

> Hi, Mike,
> 
> That's a question to which you can find an answer in Dave Pawson's FAQ at
> http://www.dpawson.co.uk/xsl/sect2/N2696.html
> 
> In your case, something like the following will do the trick:
> 
> <xsl:template match="page[not(@tab=following::page/@tab)]">
>   <!-- Process the page nodes with unique values for the tab attribute
> here -->
> </xsl:template>

What I ended up doing is the following:

<xsl:for-each select="page">
    <xsl:variable name="prev" select="preceding-sibling::page[position()=1]"/>
    <xsl:if test="not($prev) or @tab!=$prev/@tab">

I'm not sure how this differs from your method but I found that a)
[position()=1] must be used to isolate only the immediate sibling and b)
the @tab!=$prev/@tab strangely returns false if $prev is nil.

Mike

> You can do the same trick in the select attributes of apply-templates or
> for-each instructions, too, depending on exactly what you need to do.
> 
> Jay Bryant
> Bryant Communication Services
> 
> 
> ----- Original Message ----- 
> From: "Michael B Allen" <mba2000@xxxxxxxxxx>
> To: <xsl-list@xxxxxxxxxxxxxxxxxxxxxx>
> Sent: Thursday, December 01, 2005 3:53 PM
> Subject:  Exclude by Sibling Condition
> 
> 
> > Considering the following XML fragment:
> >
> >   <page name="p0" tab="products"/>
> >   <page name="p1" tab="products"/>
> >   <page name="p2" tab="products"/>
> >   <page name="d" tab="downloads"/>
> >   <page name="s" tab="support"/>
> >
> > How can I select a subset that excludes elements with a tab attribute
> > value matching that of a previous sibling?
> >
> > Meaning I want a list with no redundant @tab values like:
> >
> >   <page name="p0" tab="products"/>
> >   <page name="d" tab="downloads"/>
> >   <page name="s" tab="support"/>
> >
> > Thanks,
> > Mike