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Re: Naive question about the use of anyType

From: Henry S. Thompson <ht@cogsci.ed.ac.uk>
Date: 16 Jan 2003 09:35:22 +0000
To: <jim@ironringsoftware.com>
Cc: <xmlschema-dev@w3.org>
Message-ID: <f5bof6h77z9.fsf@erasmus.inf.ed.ac.uk>

<jim.murphy@pobox.com> writes:

> But, it made my wonder why derivation by extension type
> compatibility isn't the default - so called or record width sub-typing?
> That way as long as I provide the essential elements/attributes
> described in the schema I'm alright and it's not an error if I happen to
> include more.
>  
> I realize I bring an OO bias to XML so I was curious why this decision
> was made...

There was a _lot_ of discussion about this during the design phase,
under the general heading of 'open content models', but in the end the
consensus was to stay closer to compatibility with DTDs, and require
explicit use of <any> to open things up.

We haven't had a lot of pushback on this -- in particular, I don't think
anyone has submitted a candidate requirement for version 1.1 in this
area.

ht
-- 
  Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
          W3C Fellow 1999--2002, 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/
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Received on Thursday, 16 January 2003 04:35:19 GMT

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