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E1-21 Error

From: Stanley Guan <stanley.guan@oracle.com>
Date: Tue, 18 Mar 2003 10:31:14 -0800
Message-ID: <094601c2ed7c$8f01c260$c5b42382@us.oracle.com>
To: <www-xml-schema-comments@w3.org>
Cc: "Henry S. Thompson" <ht@cogsci.ed.ac.uk>


I think the description "Unless B is the content model wildcard of the
ur-type definition," in
the following correction is unnecessary because you won't have a case that
can reach
here and have B be the content model wildcard of the ur-type definition.

The normal case that reaches "Schema Component Constraint: Particle
Derivation OK
(Any:Any -- NSSubset)" is an example as given below.  If my thinking is
wrong, please
give an example that can illustrate what the description tries to elaborate.

My understanding of ur-type is as such: an element can be ur-type.  But, for
Derivation OK checking, it will reach "Schema Component Constraint: Particle
Restriction OK (Elt:Elt -- NameAndTypeOK)" instead of "Any:Any -- NSSubset".



Schema Component Constraint: Particle Derivation OK (Any:Any -- NSSubset)

For a wildcard particle to be a ·valid restriction· of another wildcard
particle all of the following must be true:
1 R's occurrence range must be a valid restriction of B's occurrence range
as defined by Occurrence Range OK (§3.9.6).
2 R's {namespace constraint} must be an intensional subset of B's {namespace
constraint} as defined by Wildcard Subset (§3.10.6).
3 Unless B is the content model wildcard of the ·ur-type definition·, R's
{process contents} must be identical to or stronger than B's {process
contents}, where strict is stronger than lax is stronger than skip.

The exception to the third clause above for derivations from the ·ur-type
definition· is necessary as its wildcards have a {process contents} of lax,
so without this exception, no use of wildcards with {process contents} of
skip would be possible.
<?xml version="1.0"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">

  <xsd:complexType name="baseType1" mixed="true">
    <xsd:sequence minOccurs="0" maxOccurs="unbounded">
      <xsd:any namespace="##any" processContents="lax"/>
  <xsd:complexType name="baseTitleType">

      <xsd:restriction base="baseType1">
        <xsd:sequence minOccurs="0" maxOccurs="unbounded">
          <xsd:any namespace="##any" processContents="skip"/>

  <xsd:element name="root"/>

Received on Tuesday, 18 March 2003 13:33:54 UTC

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