- From: Henry S. Thompson <ht@cogsci.ed.ac.uk>
- Date: 24 Feb 2001 21:42:17 +0000
- To: "Roger L. Costello" <costello@mitre.org>
- Cc: xmlschema-dev@w3.org
"Roger L. Costello" <costello@mitre.org> writes:
> Hi Folks,
>
> XSV is generating an error when a no-namespace schema (containing
> components that reference one another) is <include>d into a schema with
> a targetNamespace.
>
> Consider this no-namespace schema:
>
> <?xml version="1.0"?>
> <xsd:schema xmlns:xsd="http://www.w3.org/2000/10/XMLSchema"
> elementFormDefault="qualified">
> <xsd:complexType name="CardCatalogueEntry">
> <xsd:sequence>
> <xsd:element name="Title" type="xsd:string"/>
> <xsd:element name="Author" type="xsd:string"/>
> <xsd:element name="Date" type="xsd:string"/>
> <xsd:element name="ISBN" type="xsd:string"/>
> <xsd:element name="Publisher" type="xsd:string" />
> </xsd:sequence>
> </xsd:complexType>
> <xsd:element name="Book" type="CardCatalogueEntry"/>
> </xsd:schema>
>
> This schema has two components - a complexType CardCatalogueEntry
> component and an element Book component. The Book component references
> the CardCatalogueEntry component.
>
> Consider what happens when these components are included in a schema
> with a namespace.
>
> <?xml version="1.0"?>
> <xsd:schema xmlns:xsd="http://www.w3.org/2000/10/XMLSchema"
> targetNamespace="http://www.library.org"
> xmlns="http://www.library.org"
> elementFormDefault="qualified">
> <xsd:include schemaLocation="BookCatalogue.xsd"/>
> <xsd:element name="Library">
> <xsd:complexType>
> <xsd:sequence>
> <xsd:element name="BookCatalogue">
> <xsd:complexType>
> <xsd:sequence>
> <xsd:element ref="Book"/>
> </xsd:sequence>
> </xsd:complexType>
> </xsd:sequence>
> </xsd:complexType>
> </xsd:element>
> </xsd:schema>
>
> Note that the targetNamespace is the default namespace. When the
> no-namespace components (Book and CardCatalogueEntry) are included in
> this schema they take on the targetNamespace. Consequently, this
> element declaration in the no-namespace schema:
>
> <xsd:element name="Book" type="CardCatalogueEntry"/>
>
> should be referencing a CardCatalogueEntry component in the
> targetNamespace. [Or, is Book still referencing CardCatalogueEntry in
> no-namespace? Do only the components take on the namespace of the
> <include>ing schema, or do the references also take on the namespace? I
> am not clear on this.]
It should be clarified that the reference is resolved to the chameleon
component.
> When I ran this example in XSV I got this error message:
>
> Undefined type {None}:CardCatalogueEntry referenced as type definition
> of Book
XSV is in error here.
> There are two possibilities:
>
> {1} XSV has a bug and type="CardCatalogueEntry" is a reference to the
> CardCatalogueEntry in the default namespace (which in my schema is the
> targetNamespace)
Yes.
> {2} There is no bug in XSV and type="CardCatalogueEntry" is a reference
> to the CardCatalogueEntry in no-namespace, and XSV's error message is
> valid.
No.
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 Saturday, 24 February 2001 16:42:21 UTC