2011/1/2 David Carlisle <davidc@xxxxxxxxx>:
> <xsl:key name="id" match="*[@xml:id]" use="@xml:id"/>
>
> ....
>
> key('id','foo')...
>

Ah, O.K.  I never quite understood what the key element/function was
for, but now it becomes clearer.  Thanks very much!

Thomas W.