RE: document('') and URIResolver

> While in principle it would be possible for a system to special case
> this argument to document() and instead of reparsing the XML just to
> re-use some in-memory tree constructed when the stylesheet was parsed,
> this might be difficult in practice for a system to achieve as for
> example the default white space stripping rules are different, and a
> system might have done other in-place changes to teh stylesheet tree,
> for example related to processing xsl:include or code-re-writing in a
> code optimiser...

Yes; in fact, the processor might well not have the original source
stylesheet tree still available at run-time, and it almost certainly won't
have all the original whitespace. There are also complications because
document("") does NOT select the current stylesheet module; it selects the
resource whose URI is the same as the base URI of the element containing the
call on document() - which might not be the same, for example, if the
stylesheet module was assembled from external XML entities.

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