Re: [xsl] use-when attribute?

[Bruce D'Arcus <bdarcus@xxxxxxxxxxxxx>]

On Dec 17, 2004, at 3:50 AM, Michael Kay wrote:

> However, I'm not sure whether this is the right design for your 
> problem. I
> would be inclined to stick with the traditional approach: the
> special-purpose stylesheet module (here, the XHTML output module) 
> should
> import the general-purpose module, not the other way around; and you 
> then
> decide which special-purpose module to use by using that as your entry 
> point
> to the transformation.

Thinking about this more, I'd like to adopt this approach for the 
output side.

This still leaves me with the input problem.  I have this as my key 
input document dependent variable:

	<xsl:variable name="citerefs" select="//db:biblioref/@linkend"/>

Is there some elegant way to use the correct xpath expression depending 
on the input document?

An "if then else" works if there's only two options, but I'll have more 
than that.

I suppose one obvious approach would be this ...

	<xsl:variable name="citerefs" select="//db:biblioref/@linkend |
									//cite:biblioref/@cite:key |
									//tei:cit/@href"/>

.... but I'm worried that's a bad idea from a performance standpoint.  
Any other alternatives?

Bruce