Yang,
I doubt there will be a performance hit. One or the other should
evaluate to an empty set right away. 

Ciao Chris

XML/XSL Portal
http://www.bayes.co.uk/xml


> -----Original Message-----
> From: owner-xsl-list@xxxxxxxxxxxxxxxxxxxxxx 
> [mailto:owner-xsl-list@xxxxxxxxxxxxxxxxxxxxxx] On Behalf Of 
> E100 SFYang
> Sent: 20 December 2001 09:07
> To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> Subject:  RE: Re: How to express a select attr in 
> for-each for conditional or nonconditonal case.
> 
> 
> Hi,  Chris,
> Thanks for the good  solution,   I can see your point now; 
>  
> > Chris writes
> >Ok you want
> ><xsl:for-each
> select="$source[contains($keywrd,.)]|$source[$keywrd='']">
> 
> The select attr  is actually expressed from union of two 
> sets,   this is
> something I can use from now on.
> Just for curiosity, will it cost some speed performance  by 
> going through two patterns each time?  Or a better solution 
> for what I want to achieve?
> 
> regards
> Sun-fu Yang
> 
> sfyang@xxxxxxxxxxxxx
> 
> 
>  XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list
> 
> 


 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list