> 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/