RE: [xsl] combining multiple documents

> there is the documents that have in fact been 
> processed. I think it is only these that I am concerned with. 

There is no such concept in XSLT as "the set of documents that have been
processed". Anything involving a past tense like this is suspicious - it
means that the result would be dependent on the order of evaluation of
instructions in the stylesheet (which is a far greater evil than a context
dependency). You could talk about the set of all documents that are
processed by the transformation, but this is not known until the
transformation is finished.

Michael Kay
http://www.saxonica.com/