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Re: complexType derivation issue

From: Henry S. Thompson <ht@cogsci.ed.ac.uk>
Date: 12 Sep 2000 21:02:04 +0100
To: Cedric Thienot <cthienot@acland.fr>
Cc: www-xml-schema-comments@w3.org
Message-ID: <f5bog1t2xc3.fsf@cogsci.ed.ac.uk>
Cedric Thienot <cthienot@acland.fr> writes:

> Dear all,
> 
> I'm not very clear with a derivation constraint in the document
>    XML Schema Part 1: Structures   W3C Working Draft 7 April 2000
> 
> You can find in 5.11 Complex Type Definition Constraints :
>     ..
>     Constraint on Schemas: Derivation Valid (Extension)
>             If the {derivation method} is extension:
>             1.1
>                 If the {base type definition} is a complex type
> definition:
>                 ...
>                 1.1.4  The {content type} of the complex type itself
> must not be a simple type definition;
>     ...
> 
> Does it mean that the following schema is not valid:
> 
>     <complexType name="t1" base="integer" derivedBy="extension">
>         <attribute name="a1" base="integer"/>
>     </complexType>
>     <complexType name="t2" base="t1" derivedBy="extension">
>         <attribute name="a2" base="integer"/>
>     </complexType>
> 
> And if it is true, I don't really see why.

I think you're right, there's no reason for this, and at this late
date I can't figure out why it was there.  Will be fixed in next PWD.

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 Tuesday, 12 September 2000 16:02:08 UTC

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