>  I need to check if there are ancestor element nodes of an 
> element node which contains @task=$taskNumber, so I have:
> 
> <xsl:when test="descendant::*[@task = $taskNumber]">
> 	... do something
> </xsl:when>

Your title and your code talk about testing for descendants, but your
message talks about testing for ancestors - which do you mean?
> 
> ...no problem so far...but I also want to make sure that this 
> ancestor element node does not have an @result attribute. I 
> can't figure out how to do that. 

Assuming you mean descendants, 

test="descendant::*[@task = $tasknumber and not(@result)]"

Michael Kay
Software AG
home: Michael.H.Kay@xxxxxxxxxxxx
work: Michael.Kay@xxxxxxxxxxxxxx 


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