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Re: I need help with some schema problems

From: Edwin Dankert <edankert@cladonia.com>
Date: Tue, 6 Jan 2004 13:24:46 -0000
To: xmlschema-dev@w3.org
Message-ID: <bted27$9oi$1@sea.gmane.org>

Thanks, sorry forgot about that.

Having studied the problem in a bit more depth:

http://www.w3.org/TR/xmlschema-1/#rcase-MapAndSum

If I understand it correctly, you are trying to restrict your 'choice' with
a 'sequence' which is perfectly fine as long as:

1 "there is a complete order-preserving functional mapping from the
   particles"

  and

2 "The pair consisting of the product of the {min occurs} of R and the
  length of its {particles} and unbounded if {max occurs} is unbounded
  otherwise the product of the {max occurs} of R and the length of its
  {particles} is a valid restriction of B's occurrence range"

1: I read this as (roughly translated):

   Any result that is valid against the 'restricted sequence'
   should also be valid when validated against the base.

   The base is:
   <xs:choice maxOccurs="unbounded" minOccurs="0">
     <xs:element ref="a"/>
     <xs:element ref="b"/>
     <xs:element ref="c"/>
   </xs:choice>

   You are restricting this with:
   <xs:sequence maxOccurs="1" minOccurs="1">
     <xs:element ref="a"/>
     <xs:element ref="b"/>
   </xs:sequence>

   The result would be something like this:
   <root>
     <a/>
     <b/>
   </root>

   Which would be valid according to both the restriction and the base.

2: the calculated 'occurence range' (2,2) also seems to be a valid
   restriction of the base.

I think that (to my surprise) Xerces might be wrong in this case?

Regards,
Edwin
Received on Tuesday, 6 January 2004 08:26:34 GMT

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