- From: Henry S. Thompson <ht@inf.ed.ac.uk>
- Date: Wed, 28 Jan 2004 11:36:03 +0000
- To: "Michael Kay" <mhk@mhk.me.uk>
- Cc: <xmlschema-dev@w3.org>
"Michael Kay" <mhk@mhk.me.uk> writes: > The rules make it pretty clear that you can't have an xs:sequence or > xs:choice containing an xs:all, so the following is not allowed: > > <xs:sequence> > <xs:element ref="a"/> > <xs:all> > <xs:element ref="b"/> > <xs:element ref="c"/> > </xs:all> > </xs:sequence> > > Is there a rule that bans the equivalent: > > <xs:sequence> > <xs:element ref="a"/> > <xs:group ref="g"/> > </xs:sequence> > > <xs:group name="g"> > <xs:all> > <xs:element ref="b"/> > <xs:element ref="c"/> > </xs:all> > </xs:group> The intention was that Schema Component Constraint: All Group Limited [1] would rule this out, but the wording wasn't as clear as it should have been, so erratum E1-26 [2] was added to clarify this: Schema Component Constraint: All Group Limited When a model group has {compositor} all all of the following must be true: 1. It appears only as the value of one or both of the following properties: 1.1 the {model group} property of a model group definition. 1.2 the {term} property of a particle with {max occurs}=1 which is part of a pair which constitutes the {content type} of a complex type definition. This rules out your second example above, and your subsequent question about extension, since in neither case is 1.2 satisfied. ht [1] http://www.w3.org/TR/xmlschema-1/#cos-all-limited [2] http://www.w3.org/2001/05/xmlschema-errata.html#e1-26 -- 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/ [mail really from me _always_ has this .sig -- mail without it is forged spam]
Received on Wednesday, 28 January 2004 06:36:17 UTC