Barnum wrote:

> I was wondering what preceding-sibling:: means in a node-set that is
> selected from another node-set.
> 
> E.g., I make a results node-set from fruits:
>         <xsl:variable name="results" select="$fruits[color/
> @name='red']"/>
> Then I use preceding-sibling:: in another select:
>         <xsl:variable name="ids" select="$results[color/
> @name=preceding-sibling::color/@name)]"/>
> 
> Does preceding-sibling:: "point to" the preceding in fruits or results
> here?

If you write a predicate expression in square brackets then that 
expression is applied to each node in the node set before the predicate 
meaning with
   $results[color/@name=preceding-sibling::color/@name)]
the predicate expression
   color/@name=preceding-sibling::color/@name)
is applied to each node in $results and that way each node in $results 
is the context node in expressions like
   color/@name
as well as for
   preceding-sibling::color/@name
So
   color
selects child elements named 'color' for each node in $results
and
   preceding-sibling::color
selects preceding sibling elements named 'color' for each node in $results.

In that way preceding-sibling::color inside a predicate is not different 
to any other axis use.





-- 

	Martin Honnen --- MVP XML
	http://msmvps.com/blogs/martin_honnen/