Identity Constraints in Multiple Elements II

Hi,

Some days ago I sent a email asking if a strange Xerces error was a bug acording
to the Specification.

I got this error :
 Schema Error: More than one identity constrain named XXXX
And in my schema only appeared once the identity constraint XXX.
(But the complexType, where the identity constraint appeared, was used several
times)
Henry Thompson answared me that there is no problem with this, and thus the
error message was a Xerces bug.

But...
I tried to reproduce the error in a small schema to report the Bug to the Xerces
devolopers. But for my surprise I couln't reproduce it.
Later I discovered that the problem was in a referenced <group> element. (If I
write an equivalent schema without the group element I don't get the error)

My question is another time the same. I get the same error with this minimized
schema. Is this schema incorrect or it's a Xerces bug?
I ask this, because I don't know if I have some misunterstanding with <groups>

    <group name="GElementType">
        <choice>
            <element name="Struct" type="spe:TStruct">
                <unique name="NameStruct">
                    <selector xpath="*"/>
                    <field xpath="@name"/>
                </unique>
            </element>
            <element name="Scalar" type="spe:TScalar">
                <unique name="NameScalar">
                    <selector xpath="Attribute"/>
                    <field xpath="@name"/>
                </unique>
            </element>
        </choice>
    </group>

    <complexType name="TStruct">
        <choice maxOccurs="unbounded">
            <group ref="spe:GElementType"/>
        </choice>
        <attribute name="name" type="NCName" use="required"/>
    </complexType>

    <complexType name="TScalar">
        <attribute name="name" type="NCName" use="required"/>
    </complexType>

A lot of thanks.

I enclude the original mail for reference: 

"Henry S. Thompson" wrote:
> 
> Joan Pujol <joan.pujol@ima.udg.es> writes:
> 
> > Hi,
> >
> > I have some problems using a Schema with Xerces 1.4.
> > I think that it's a Xerces bug, because the Schema go ok with XSV.
> > But I want to consult you before reporting a bug.
> >
> >
> > I have some Unique Identity constraints that only appears ONCE in
> > the schema.  But these identity constraints are in elements that are
> > in Global Complex Types.  Then there are several elements of these
> > complextypes included in the Root Element.
> >
> > It is correct?
> 
> Should be fine.
> 
> > Because Xerces says me:
> > Schema Error: More than one identity constraing named X....
> 
> That sounds like a bug. . .
> 
> 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/

-- 
---
Joan Jesús Pujol Espinar
PTS Sistemes Departament IMA

Received on Friday, 30 November 2001 03:43:50 UTC