RE: Comments on XPath Filter 2.0 draft (2002-06-20)

Merlin,

> r/gregor.karlinger@iaik.at/2002.07.10/09:26:32
> >Wouldn't it be sufficient to have instructions like:
> >
> >  Process each node in the document, adding each node to the  filter 
> > node-set if and only if the node is present in any  
> subtree-expanded 
> > union node-set and all subsequent  subtree-expanded intersect 
> > node-sets but no subsequent  subtree-expanded subtract 
> node-sets, or 
> > false otherwise.  If there are no subsequent intersect or subtract 
> > node-sets,  then that part of the test is automatically passed.
> >
> >Regards, Gregor
> 
> That sounds perfect to me; I'd change "the document" at the 
> start to "the input node-set" and "the filter node-set" to 
> "the output node-set". Then I'd follow with this:

This is fine, since it implicitely includes the final set intersection.

>   Presence in a subtree-expanded node-set can be efficiently 
> determined
>   without actually expanding the node-set, by simply maintaining a
>   stack or count that identifies whether any nodes from that node-set
>   are an ancestor of the node being processed.

Fine again.

Regards, 
Gregor