RE: [xml-dev] Problems with xs:redefine

[Kasimier Buchcik <K.Buchcik@4commerce.de>]

Hi,

On Thu, 2005-11-24 at 13:55 +0000, Michael Kay wrote:
> > Potential bug in Saxon 8.5.1: I noticed that it does not fire an
> > UPA error for the above scenario; on the other hand it does fire the
> > error if the @ref attributes are substituted for @name attributes.
> > A "different/same element declaration" issue?
> 
> Yes, Saxon is testing only that the element declaration is unambiguously
> identified; if two distinct particles refer to the same declaration, Saxon
> doesn't report an error. It's a known and published limitation of Saxon that
> it doesn't implement this bug in the spec ;-)

A 'same declaration' could also be an identical component, couldn't it?
If yes, then shouldn't the following model be accepted by Saxon as well?
I'm a bit scared of the necessity of component identity checks here.

<xs:choice>
    <xs:element name="a"/>
    <xs:element name="b"/>
    <xs:sequence>
        <xs:element name="a"/>
        <xs:element name="b"/>
    </xs:sequence>
</xs:choice>

Regards,

Kasimier