Re: [xsl] Problem of template priority

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

At 2010-04-29 01:41 +0100, Fabre Lambeau wrote:
> I have a complex XSLT stylesheet, which does import some other ones 
> in order to refine/delegate some of the work depending on the type 
> of data it finds.
> This works by using templates with modes, and matching rules that 
> are more specific, hence increasing their default priority. However, 
> in the main sheet (the one that imports the others), there is a case 
> where I want to force the most generic template to be applied, after 
> which it can call the others.

Well, importance trumps priority.  The lowest priority template in 
the importing stylesheet is more important than the highest priority 
template in the imported stylesheet.  So if I understand you above, 
that's what you get in XSLT.

> However, no matter what I do with the priority attribute, my 
> processor seems to always select the template from the imported stylesheet.

That surprises me.

> Having said that, I tried to create a simple example (below), and 
> there I get just the opposite effect: I can never get the imported 
> template to apply instead of the generic one, even though it is more selective
>
> === Main sheet ===
>
> <xsl:stylesheet version="2.0" 
> xmlns:xsl="http://www.w3.org/1999/XSL/Transform";>
>     <xsl:import href="./special.xsl"/>
>
>     <xsl:template match="/">
>         <xsl:apply-templates mode="process-record"/>
>     </xsl:template>
>
>     <xsl:template mode="process-record" match="feed" priority="-9">
>         <helloworld>
>             <xsl:next-match/>
>         </helloworld>
>     </xsl:template>
> </xsl:stylesheet>
>
> === Imported sheet ===
>
> <xsl:stylesheet version="2.0" 
> xmlns:xsl="http://www.w3.org/1999/XSL/Transform";>
>     <xsl:template mode="process-record" 
> match="feed[@type='special']" priority="10">
>         <specialone/>
>     </xsl:template>
> </xsl:stylesheet>
>
> === Document ===
>
> <feed type="special">
>         <node/>
> </feed>
>
>
> With this example, no matter what value I give to the priority 
> attributes, I always get the following result:
>
> <helloworld>
>         <specialone/>
> </helloworld>

Which is exactly what I would expect:  the importing stylesheet is 
adding the <helloworld> and the <xsl:next-match/> is then reapplying 
the last-matched node as if the last matched template didn't exist 
... and so the <specialone> is being added under <helloworld>.

The relative priorities are irrelevant.  The importance trumps any 
use of priority.

> Any idea what I'm doing wrong?

I'm lost as to what you were wanting to do "right".  You say:

  there is a case where I want to force the most generic
  template to be applied, after which it can call the others

Isn't that what you are doing above?  The template in the importing 
stylesheet is being applied and during that it "calls" the template 
in the imported stylesheet.

What result *exactly* did you want for the source document above?

. . . . . . . . . . . Ken

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