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Re: redefinition errors

From: Henry S. Thompson <ht@cogsci.ed.ac.uk>
Date: 10 Jan 2001 09:42:48 +0000
To: MarkH@i2.co.uk
Cc: xmlschema-dev@w3.org
Message-ID: <f5bwvc3kajr.fsf@cogsci.ed.ac.uk>
MarkH@i2.co.uk writes:

> > -----Original Message-----
> > From: ht@cogsci.ed.ac.uk [mailto:ht@cogsci.ed.ac.uk]
> > Sent: 09 January 2001 13:45
> > 
> > Which part of 'same name, same content model, different type' doesn't
> > make this clear?  The scope is a content model.
> I'm a practitioner learning on the job with nowhere near as much time as I'd
> like to sit back and read the breadth before dipping into making something.
> So I'm still unfamiliar with the terminology and all the areas of the very
> extensive spec compared to many of the people on this list, and I have to
> confess that I don't know what the scope of a "content model" is. 
> It's easy when you know this stuff inside out, but very difficult to know
> when a quick look at the spec (which bit? what keywords will help you find
> it? etc.) will solve a problem. So as I write this I'm non the wiser. I'll
> look at the spec to see what a content model is.
> I know that probably makes me sound stupid. I don't mind, because I know
> that I'm not.

Sorry if you understood me to be insulting your intelligence.  I made
a mistake I should recognise by now, namely assuming the XML DTD
terminology was common knowledge, which of course it isn't.

Forget that, then.  In the XML Schema context, here's the relevant
text [1]:

  "If the {particles} [of a model group] contains, either directly,
  indirectly (that is, within the {particles} of a contained model
  group, recursively) or implicitly two or more element declaration
  particles with the same {name} and {target namespace}, all their
  {type definition}s must be the same."

A model group is (the schema component corresponding to) a <choice>,
<all> or <sequence>.

Hope this helps


[1] http://www.w3.org/TR/xmlschema-1/#cos-element-consistent
  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 Wednesday, 10 January 2001 04:42:51 UTC

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