W3C home > Mailing lists > Public > www-xml-schema-comments@w3.org > October to December 2000

Re: simpleTypes and final

From: Henry S. Thompson <ht@cogsci.ed.ac.uk>
Date: 26 Oct 2000 09:00:54 +0100
To: "Bob Schloss/Watson/IBM" <rschloss@us.ibm.com>
Cc: www-xml-schema-comments@w3.org, "Paul V. Biron" <Paul.V.Biron@kp.org>
Message-ID: <f5blmvchw09.fsf@cogsci.ed.ac.uk>
"Bob Schloss/Watson/IBM" <rschloss@us.ibm.com> writes:

> First, congratulations on release CR specs....
> 
> A question:
> 
> The Primer (24 Oct) section 4.8 paragraph 2 says that you can prevent
> a particular simple type from having types derived from it.

I think you're right that this is at best misleading.


> The Datatype spec (24 Oct) section 5.1 does not indicate that the
> final attribute can be specified on the simpleType element information
> item.

What is provided is a way of preventing derivations which change
particular facets.  If you say e.g.

  <minInclusive value="10" fixed="true"/>

then derived types cannot change minInclusive (or minExclusive, right
Paul?).

If, somewhat tediously, you set fixed on _all_ the constraining facets 
of a simple type, that would effectively block further derivation.

It has to be said one reason that overall blocking is not easier wrt
simple types is we had never had anyone signal a requirement -- do you 
have such a requirement?

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, 26 October 2000 04:00:58 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Sunday, 6 December 2009 18:12:49 GMT