Thanks Sandy,
I'm glad that schema 1.1 is going to fix this. MapAndSum doesn't really
achieve what it's intended for.
Even if I fool the "remove pointless particles" process by adding
minOccurs/maxOccurs, this case doesn't get handled properly:
Base = (A|(B,C){2})
Restriction = (B,C){2}
I'll be eagerly awaiting the 1.1 version :)
--Martin
p.s. FYI, "[Error] foo.xsd:184:30: rcase-MapAndSum.2: Group's occurrence range,
(4,4), is not a valid restriction of base group's occurrence range, (1,1)."
Note that the reported number is double, thanks again to MapAndSum.
On 2010-09-24 at 03:28:56, Sandy Gao wrote:
> Martin,
>
> Xerces is doing what the schema 1.0 spec requires. It's the "remove
> pointless particles" that's causing the problem. See clause 2.2 of [1].
>
> So after the removal process, (ii) to (iv) all become (A,C,D). Now the
> base has a sequence of 2 items but the restriction has 3 items.
>
> This does look strange, which is why in schema 1.1 [2], the 5x5 table
> is
> replaced by a rule similar to "as long as the restriction doesn't allow
> more than the base".
>
> XSV accepts the schema docs because it's been updated to use the 1.1
> rules for particle restriction. In Xerces we are working on
> implementing
> schema 1.1, on a branch. The new particle restriction rules are not
> available yet.
>
> [1]
> http://www.w3.org/TR/2004/REC-xmlschema-1-20041028/#cos-particle-
> restric
> t
> [2] http://www.w3.org/TR/xmlschema11-1/
>
> Thanks,
> Sandy Gao
> XML Technologies, IBM Canada
> Editor, W3C XML Schema WG <http://www.w3.org/XML/Schema>
> (1-905) 413-3255 T/L 313-3255
>
> From:
> "Thomson, Martin" <[email protected]>
>
> To:
> "[email protected]" <[email protected]>
>
> Date:
> 2010-09-23 12:19 AM
>
> Subject:
> Simple nested restriction
> ________________________________
>
>
>
>
> I'm trying to understand why Xerces is rejecting what appears to be a
> simple restriction.
>
> The base type permits either of A,B or A,C,D; the restricting types
> simply remove the choice:
>
> Base = (A,(B|(C,D)))
> i. Restriction = (A,B) -- OK
> ii. Restriction = (A,C,D) -- Not OK
> iii. Restriction = (A,(C,D)) -- Not OK
> iv. Restriction = (A,((C,D)|)) -- Not OK
>
> As the last two examples show, mimicking the structure of the base type
> with choices and sequences is too easily collapsed this to bluff it.
>
> I get the impression that this is related to MapAndSum [1]. From my
> uneducated reading, it seems like MapAndSum never considered the simple
> case where the sequence mapped entirely to one of the particles of the
> choice.
>
> XSV [2] accepts all four forms.
>
> I can see how this might be viewed as a valid interpretation of the
> specification, but it's a real nuisance. Should I raise a bug report
> on
> this?
>
> Cheers,
> Martin
>
> [1] http://www.w3.org/TR/xmlschema-1/#rcase-MapAndSum
> [2] http://www.w3.org/2001/03/webdata/xsv
>
