Re: [xsl] XPath for matching multiple child elements

["Dimitre Novatchev" <dnovatchev@xxxxxxxxx>]

Probably this would be faster?

<xsl:stylesheet version="2.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
>

<xsl:key name="kComDesc" match="h1|p|b|i"
  use="exists(ancestor::Comments[1])"/>

<xsl:template match="key('kComDesc', 'true')">
  Whatever processing here
</xsl:template>
</xsl:stylesheet>


--
Cheers,
Dimitre Novatchev
---------------------------------------
Truly great madness cannot be achieved without significant intelligence.
---------------------------------------
To invent, you need a good imagination and a pile of junk
-------------------------------------
You've achieved success in your field when you don't know whether what
you're doing is work or play


On 9/28/06, Michael Kay <mike@xxxxxxxxxxxx> wrote:
> > But it's free enough to support a bit of a workaround, even
> > if you have no schema:
> >
> > <xsl:variable name="comment-elements"
> > select="//comments//(h1|p|b|i)"/>
> >
> > <xsl:template match="*[exists(. intersect $comment-elements)]">
> >     ...
> > </xsl:template>
> >
> > I think this should work.
>
> Yes, but it might have fairly horrible performance.
>
> I don't know how other processors work, but with Saxon, patterns are a lot
> more efficient if they identify the element names that match, because Saxon
> basically does a hash lookup on the node kind and then on the node name. Any
> match="*" pattern gets tested against every node; and in this case that will
> involve a serial search through the list of h1|p|b|i elements, which is
> distinctly O(n^2). Not worth the savings in keystrokes.
>
> Michael Kay
> http://www.saxonica.com/