- From: Henry S. Thompson <ht@cogsci.ed.ac.uk>
- Date: 14 Feb 2002 12:13:01 +0000
- To: Jeni Tennison <jeni@jenitennison.com>
- Cc: Mark Feblowitz <mfeblowitz@frictionless.com>, "Xmlschema-Dev (E-mail)" <xmlschema-dev@w3.org>
Jeni Tennison <jeni@jenitennison.com> writes:
> Hi Mark,
>
> > We have been using the second approach, and it is very elegant. The
> > ability to target plug-in content without disturbing the surrounding
> > context is very cool. It does, however, get very complicated when
> > the type hierarchy gets deeper. That's also when restriction and
> > extension come into conflict, because substitution groups want their
> > descendants to be restrictions.
>
> I think that the members of substitution groups' types only need to be
> *derived* from the type of the head of the substitution group, not
> necessarily restrictions?
Correct. Derivation by extension or restriction is OK.
ht
--
Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
W3C Fellow 1999--2001, part-time member of W3C Team
2 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- (44) 131 650-4440
Fax: (44) 131 650-4587, e-mail: ht@cogsci.ed.ac.uk
URL: http://www.ltg.ed.ac.uk/~ht/
Received on Thursday, 14 February 2002 07:13:06 UTC