I have it on reasonably good authority (somebody at a high
level at Altova)
that the internal XSL engine used in XML Spy 5.* for
debugging is a variant of Saxon, not of MSXML.
If this is so, then they have disguised it very effectively. The error
messages are completely different from Saxon's, and it has completely
different bugs - ten minutes' experimenting showed that it doesn't allow
forwards references to global variables, and it displays number(0.00005)
as "0". It also signals some errors that Saxon recovers from.
(But I did find one bug in common - they don't required xsl:param to be
the first instruction in a template, which is a bug that was in Saxon
6.5.2 and earlier releases).
If their product was derived from Saxon, then under the Mozilla Public
License they would be obliged to make their source code freely
available.
Michael Kay
Software AG
home: Michael(_dot_)H(_dot_)Kay(_at_)ntlworld(_dot_)com
work: Michael(_dot_)Kay(_at_)softwareag(_dot_)com
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