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Re: Determinization in case of ambiguity or Should XML validators report on schemas that violate the UPA constraint?

From: Henry S. Thompson <ht@inf.ed.ac.uk>
Date: Mon, 16 Apr 2007 10:02:06 +0100
To: "Shlomo Yona" <S.Yona@F5.com>
Cc: <xmlschema-dev@w3.org>
Message-ID: <f5b7isclmk1.fsf@hildegard.inf.ed.ac.uk>

Hash: SHA1

Several problems with your schema:

 1) xs:all is only allowed at the top level of a content model;
 2) targetNamespace and default namespace don't line up.

Fixing those two problems does indeed leave a schema wrt which XSV
reports a UPA violation:

   <schemaError char="25" line="6" phase="instance"
    resource="upa3.xsd">non-deterministic content model for type None: {foo}:b/{foo}:b</schemaError>

Since the schema is broken, your question about the validity of a
particular instance is a bit odd - you can't expect interoperable
behaviour.  For what it's worth, if you tell XSV to keep going and
try to validate the instance anyway, it reports no instance errors,
but you really can't conclude very much from that. . .

- -- 
 Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
                     Half-time member of W3C Team
    2 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- (44) 131 650-4440
            Fax: (44) 131 650-4587, e-mail: ht@inf.ed.ac.uk
                   URL: http://www.ltg.ed.ac.uk/~ht/
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Received on Monday, 16 April 2007 09:02:20 UTC

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