- From: Henry S. Thompson <ht@cogsci.ed.ac.uk>
- Date: 05 Sep 2001 12:48:17 +0100
- To: Holger.Joukl@LBBW.de
- Cc: xmlschema-dev@w3.org
Holger.Joukl@LBBW.de writes:
> Hello there,
> I wonder about the minOccurs and maxOccurs properties for the
> element declarations inside a choice model group.
> Is it allowed to define something like:
>
> ...
> <choice>
> <element name="elem1" type="string" minOccurs="0" maxOccurs="10"/>
> <element name="elem2" type="integer"/>
> </choice>
> ...
>
> I am also confused about the REC saying this in 3.8.4:
> "...
> Nothing in the above should be understood as ruling out groups whose
> {particles} is empty: although no sequence can be ·valid· with respect to
> such a group whose {compositor} is choice, the empty sequence is ·valid·
> with respect to empty groups whose {compositor} is sequence or all.
> ..."
> Does that mean I cannot validate an empty sequence (instance) against an
> empty choice group (schema), but I can validate an empty sequence
> (instance) against an empty sequence group (schema)?
Yes.
The analogy I find helpful is with the logical operators 'and' and
'or', when extended to any number of arguments. Then traditionally it
is held that and() is true, but or() is false.
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 Wednesday, 5 September 2001 07:47:53 UTC