Very good.
If these are the primary things in Schema 1.1, then this is
a big help.
Question: if we drop unordered property so that we have
xsd:sequence groups and xsd:all groups, will we retain restrictions on nesting,
i.e., can't nest xsd:all inside an xsd:all, etc.
To me there's little or no downside to these restrictions
because you can always put an element "wrapper" around an xsd:all group which
changes the logical model, but in DFDL doesn't imply anything about the physical
representation, so it's not really a problem.
I assume xsd:all will have the semantics of preserving the
arrival order, so it is much like an array of choice semantically. That is, the
DFDL infoset will have the items within the xsd:all group in the order they
appear in the physical data.
Mike Beckerle |
OGF DFDL WG Co-Chair | CTO | Oco, Inc.
Tel:
781-810-2100 | 504 Totten
Pond Road, Waltham MA 02451 | mbeckerle.dfdl@gmail.com
Sandy Gao at IBM has looked at the
reasons for moving to schema 1.1 and concluded that DFDL should move.
Grounds:
- Weakened wildcard support - there is less ambiguity in
1.1 because an optional element x followed by a wildcard will match x, instead
of giving a UPA error - this will enable DFDL to model more formats
- Relaxation of <xs:all> means that it is
suitable for DFDL use - this will allow us to drop the dfdl:unordered
property
- In Schema 1.0, annotations
are lost on particles, but they are needed by DFDL. Schema 1.1 captures all
annotations.
Regards
Steve
Hanson
Programming Model Architect
WebSphere Message Brokers
Hursley,
UK
Internet: smh@uk.ibm.com
Phone (+44)/(0) 1962-815848
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