- From: Henry S. Thompson <ht@cogsci.ed.ac.uk>
- Date: 22 Oct 2001 11:51:24 +0100
- To: "Tim Galle" <timgalle@cyberdude.com>
- Cc: <xmlschema-dev@w3.org>
"Tim Galle" <timgalle@cyberdude.com> writes: > Hello everyone, > Is the following possible with XML-schemas: > > In Schema A I define a structure (element construction) and 2 kinds of > attributes: a kind that can not be redefined (Final) and one that can be > redifined (Overridable) > > Now Schema B must take everything from A, structure and attributes. It may > extend the structure with new elements, and add new attributes to elements > defined in A. It may redefine overridable attributes from A (Polymorhing), > but it may not redefine final attributes. In brief, yes, you can do this. You have to do it attribute-by-attribute, however: A: <xs:schema targetNamespace="urn:foo1" xmlns:my="urn:foo1"> <xs:complexType name="struct1"> <xs:sequence> ... </xs:sequence> <xs:attribute name="final1" type="my:ft1"/> <xs:attribute name="final2" type="my:ft2"/> <xs:attribute name="final3" type="my:ft3"/> <xs:attribute name="over1" type="xs:decimal"/> <xs:attribute name="over2" type="xs:string"/> </xs:complexType> <xs:simpleType name="ft1" final="#all"> <xs:restriction base="xs:decimal"/> </xs:simpleType> <xs:simpleType name="ft2" final="#all"> <xs:restriction base="xs:string"/> </xs:simpleType> <xs:simpleType name="ft3" final="#all"> <xs:restriction base="xs:boolean"/> </xs:simpleType> </xs:schema> <xs:schema targetNamespace="urn:foo2" xmlns:core="urn:foo1" xmlns:ym="urn:foo2"> <xs:import "urn:foo1"/> <xs:complexType name="extStruct1"> <xs:complexContent> <xs:extension base="core:struct1"> <xs:sequence> . . . </xs:sequence> </xs:extension> </xs:complexContent> </xs:complexType> <xs:element name="xyzzy"> <xs:complexType> <xs:complexContent> <xs:restriction base="ym:extStruct1"> <xs:attribute name="over1" type="xs:integer"/> </xs:restriction> </xs:complexContent> </xs:complexType> </xs:element> </xs:schema> This is OK. If you tried to restrict "final1" instead of "over1", you'd get an error. Hope this helps, 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 Monday, 22 October 2001 06:50:38 UTC