Note: the call is scheduled for 2 hours

Agenda:

1. Go through actions.

2.  Codepage for text items in infoset.

  It is proposed that text values in the infoset should be ISO10646.

3. Annotations on Top Level element

4 .Scoping of elements and Types
MB has pointed out a problem with the current scoping rules and proposed that propoeties on an element should override those on its type.

5. Scoping rules for assert/discriminator and other annotations


6. Need for the equivalent of WTX Restart

Restart indicates where in the schema to restart parsing when unable to correctly parse content

7. Built-in Specifications
Spec Section 23 Built-in Specifications
TBD: this section gives the names, import URLs for, rep-property definition sets, property definitions, etc. for the built-in named format definitions


8. AOB


Current Actions:
No
Action
012
AP/SH: Update decimalCalendarScheme
10/9: Not allocated yet

17/9: No update

24/9: Add calendar binary formats to actions

22/10: No progress

16/1: proposal distributed and discussed. Will be redistributed

21/1: add locale,
04/02: changed from locale to specific properties

18/2: Need more investigation of ICU strict/lax behaviour.

08/04: Not discussed

22/04: AP to complete asap once the ICU strict/lax behaviour is understood.
29/04: No progress

06/05: No progress

13/05: Calendar has been added to latest spec version v034 but still a few details to clarify.
026
SH: Envelopes and Payloads
08/04: Not discussed
explicity, but recursive use of DFDL is tied up with this
22/04: Two aspects. Firstly compositional - do sufficient mechanisms exist to model an envelope with a payload that varies. Secondly markup syntax - this might be defined in the envelope.
The second of these is very much tied up with the variable markup action 028, so will be considered there. SH to verify the composition aspect.

29/04: SH and AP working on proposal. related to Action 028

06/05: No progress

06/05: No progress
027
SH: Property precedence tables
08/04: Not discussed

22/04: Two things missing from the existing precedence trees. Firstly, does not show alternates (eg, initiator v initiatorkind). Secondly, need a tree per concrete DFDL object (eg, element). SH to update.

29/04: No progress

06/05: SH is updating tables which will be ready for next call

13/05: SH emailed updated version. AP commented.. See minutes to issues.
028
SH: Variable markup
08/04: Discussed briefly at end of call, IBM to see whether there any use cases that require recursive use of DFDL.

15/04: Use case was distributed and will be discussed on next call.

22/04: The use case in question is EDI where the terminating markup for the payload segments is defined in the ISA envelope segment. The markup is modelled as an element of simple type where the allowable markup values are defined as enums on the type. But we need to handle two cases - firstly where the envelope is present, so the value used by the payload is taken from the envelope. Secondly where only the payload is present. Here we need a way of scanning for all the enum values, and adopting the one we actually find, when parsing. And using a default when unparsing. SH to explore use of a DFDL variable, where the variable has a default, but also has a type that is the same as the markup element - that way we get to use the enums without defining everything twice.

29/04: SH and AP working on proposal.

06/05: No progress

13/05: No progress
029
MB: valueCalc (output length calculation)
08/04: Not discussed

22/04: Action allocated to MB, this is to complete the work started at the Hursley WG F2F meeting.

29/04: No progress

06/05: MB will have update for next call

13/05: MB will have update for next call
032
DG: Investigate compatibility between DFDL infoset and XDM
08/04: No update

22/04: No update

29/04: No update

06/05: DG indicates will have update next week

13/05: see minutes
033
AP/TK: Assert/Discriminator semantics. AP to document. TK to check uses of discriminator besides choice.
08/04: In progress within IBM

22/04: Waiting for TK to return from leave to complete.
29/04: TK has sent examples shown need for discriminators beyond choice. Agreed. MB to respond to TK
06/05: Discussed suggestion of adding type indicator to discriminator. MB to provide examples.

15/03: Semantic documented in v034. MB to provide examples of need for scope indicator on discriminator
036
SH: Provide use case for floating component in a sequence
08/04: Raised

15/04: Use case sent and discussed. SH to do further investigation

22/04: IBM feedback from WTX team is that alternate suggested ways of modelling the EDI floating NTE segment have significant usability issues. The DFDL principle is that for a problem that can be expressed as two-layered, then two DFDL models are needed.  The EDI NTE segment does not fall into this though, as its use is on a per sequence basis.  Ongoing.
29/04: Agreed that need to be in V1. SH to make a proposal

06/05: No progress
037
All: Approach for XML Schema 1.0 UPA checks.
22/04: Several non-XML models, when expressed in their most obvious DFDL Schema form, would fail XML Schema 1.0 Unique Particle Attribution checks that police model ambiguity.  And even re-jigging the model sometimes fails to fix this. Note this is equally applicable to XMl Schema 1.1 and 1.0. While the DFDL parser/unparser can happily resolve the ambiguities, the issue is one of definition. If an XSD editor that implements UPA checks is used to create DFDL Schema, then errors will be flagged. DFDL may have to adopt the position that:
a)DFDL parser/unparser will not implement some/all UPA checks (exact checks tbd)

b) XML Schema editors that implement UPA checks will not be suitable for all DFDL models

c) If DFDL annotations are removed, the resulting pure XSD will not always be valid (ie, the equivalent XML is ambiguous and can't be modelled by XML Schema 1.0)

Ongoing in case another solution can be found.

29/04: Will ask DG and S Gao for opinion before closing

06/05: Discussed S Gao email and suggestions. Decided need to review all XML UPA rules and decide which apply to dfdl.
038
MB: Submit response to OMG RFI for non-XML standardization
22/04: First step is for MB to mail the OGF Data Area chair to say that we want to submit

29/04: MB has been in contact with OMG and will sunbit dfdl.

06/05: MB has prepared response to OMG. Will send DFDL sepc v033
039
SKK: Approach for creating Schema-For-DFDL xsds.
22/04: Resolve issue around multiple declarations needed for DFDL properties, perhaps using MB's meta approach

29/04: Don't like qualified attributes in long form. SKK to check there are no code gen implications, eg EMF.

06/05: SKK will send update by Friday
040
SH: LengthKind on complex objects.  
29/04: All send comment before next call

06/05: See minutes. Agreed to remove lengthKind from sequence and choice.
041
AP: UnorderedInitiated
29/04: All: Review for next call

06/05: See minutes: Agreed to generalize to all sequences
042
MB: Complete variable specification.
To include how properties such as encoding can be set externally. Must be a known variable name.

06/05: No progress
043
13/05:  Types in the infoset.  Currently infoset types have defined value space but that implies a parser would have to validate input. Is this correct?
044
13/05:  Bidi





Alan Powell

MP 211, IBM UK Labs, Hursley,  Winchester, SO21 2JN, England
Notes Id: Alan Powell/UK/IBM     email: alan_powell@uk.ibm.com  
Tel: +44 (0)1962 815073                  Fax: +44 (0)1962 816898






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