1.        Create an empty working set of "explicit" properties. Create an empty working set of "default" properties.

2.        Move to the innermost  schema component in the chain of references.

3.    Assemble its directly relevant "explicit" properties from its local dfdl:ref (if present) and its local properties (if present), the latter overriding the former (that is, local wins). Combine these with the current working set of "explicit" properties. It is a schema definition error if there is the same property appears twice. Result is a new working set of "explicit" properties. Obtain directly relevant "default" properties from in-scope unnamed dfdl:format block (if present).  Combine these with the current working set of "default" properties, the latter overriding the former (ie, inner wins). Result is a new working set of "default" properties.

4.   Move to the schema component that references the current component, and repeat step 3. If there is no referencing component, move to step 5.

5.        Validate the resultant set of properties. The "explicit" properties take priority, "defaults" only used when no "explicit" is present. It is a schema definition error if a required property is in neither the "explicit" nor the "default" working sets.

Note: we didn't discuss the suggested change of disallowing multiple annotations at the same point (other than for selectors) or the same property in short and long form. Please review this change.


2. Resolving points of uncertainty and parsing rules

Reviewed the latest draft (v5) that Alan had distributed. The only change was the introduction of the 'potentially  uncertain' state discussed on the call last week. Alan was not overly happy with the new concept and will try some other way of describing the problem.


3. Comments on Draft 036
No comments received. It is now available on gridforge.

4. Go through remaining actions
Actions updated below
 
5. Plan to finish DFDL v1
Alan pointed out that in order to meet the target of having the document ready for approval at the next OGF meeting we need to have all the action items resolve in the next month or so. Alan will produce an outline schedule for completing the spec.
Also discussed if there is any technical writer support available within IBM to edit the specification. Steve H will contact Sandy Gao to see who edits the XML schema specification

Next call 28 October 13:00 UK

Meeting closed, 14:30

Actions raised at this meeting

No	Action
062	SH investigate technical writer support.

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. 20/05: No Progress 27/05: No Progress 03/06: No Progress (low priority) 09/06: No Progress (low priority) 17/06: SH to check ICU code for lax calendar behaviour 24/06: no progress 01/07: no progress 15/07: no progress 29/07: no progress 05/08: no progress 12/08: no progress 19/08: Inconsistencies are being found in ICU behaviour so Calendars need reviewing again. 26/08: Specific three character short time zones may not be  maintained during round tripping when there is more than one short form for a time zone offset. Because dates and datetimes in the infoset only maintain a time zone offset so on unparsing it isn't possible to say which short form will be selected for a particular offset when there is more than one possible. Need to document. 09/09: no progress 16/09: no progress 30/09: no progress 07/10: no progress 14/10: no progress 21/10: Will produce a list of known issues.
033	MB: Need for scope indicator on discriminator 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 20/05: MB to provide examples of need for scope indicator on discriminator (but lower priority than action 029) 27/05: No Progress (lower priority) .... 19/08: No Progress (lower priority) 26/08: No Progress (lower priority) 09/09: no progress 16/09: no progress 30/09: no progress 07/10: no progress 14/10: Action re-titled and assigned to Mike B 21/10: 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. 20/05: SH or SKK to investigate 27/05: No Progress 03/06: The concern is that some dfdl schemas will fail UPA check when validation is turned on or when editted using tooling that enforces UPA checks. Renaming fields will resolve some/most issues. Need documentation  that  describes issue and best practice. 17/06: no change 24/06: no change 01/07: no prgress 15/07: No Progress (lower priority) 29/07: No Progress (lower priority) 05/08: No Progress (lower priority) 12/08: No Progress (lower priority) 19/08: Clarify that this action is to go through the XML UPA checks to assess impact on dfdl schemas and advice best practice. Name clashes is just one example. SH or SKK 26/08: No Progress (lower priority) 09/09: no progress 16/09: no progress 30/09: no progress 07/10: no progress 14/10: no progress 21/10: no progress
045	20/05 AP: Speculative Parsing 27/05: Psuedo code has been circulated. Review for next call 03/06: Comments received and will be incorporated 09/06: Progress but not discussed 17/06: Discussed briefly 24/06: No Progress 01/07: No Progress 15/07: No progress. MB not happy with the way the algorithm is documented, need to find a better way. 29/07: No Progress 05/08: No Progress. Will document behaviour as a set of rules. 12/08: No Progress 19/08: No Progress 26/08: No Progress 09/09: no progress 16/09: no progress 30/09: AP distributed proposal and others commented. Brief discussion AP to incorporate update and reissue 07/10: Updated proposal was discussed.Comments will be incorporated into the next version. 14/10: Alan to update proposal to include array scenario where minOccurs > 0 21/10: Updated proposal reviewed
049	20/05 AP Built-in specification description and schemas 03/06: not discussed 24/06: No Progress 24/06: No Progress (hope to get these from test cases) 15/07: No progress. Once available, the examples in the spec should use the dfdl:defineFormat annotations they provide. ..... 19/08: No Progress (lower priority) 26/08: No Progress (lower priority) 09/09: no progress 30/09: no progress 07/10: no progress 14/10: no progress 21/10: Discussed the real need for this being in the specification. It seemed that the main value is it define a schema location for downloading 'known' defaults from the web.
051	Scoping rules. MB: to document change to scoping rules to satisfy implementation concerns 17/06: MB and SH proposals discussed. Needs further discussion 24/06: AP to update presentation with latest proosal 24/06: AP had updated presentation. MB to review 08/07: Discussed at length. Simple types will now take annotations. Variables will be used for parameters. 15/07: No further progress. Needs final write up. 29/07: No Progress 05/08: No Progress 12/08: No Progress 19/08: AP will document new syntax rules. 26/08: No Progress 09/09: AP has documented new scoping rules. Not discussed 16/09: Not disussed. AP to update element reference examples 30/09: Significant dissatisfaction with proposed new rules. New proposal developed during call. AP to document. 07/10: New proposal was refined. Details in minutes. 14/10: Discussed at length. Details in minutes. 21/10: Discussed at length. Details in minutes.
056	resolve lenghtUnit=bits including fillbytes 12/08: No Progress 19/08: No Progress 26/08: No Progress 09/09: no progress 30/09: no progress 07/10: no progress 14/10: no progress 21/10: no progress
059	9/9: define how encoding,  byteorder and floating point format externally 16/09: no progress 07/10: no progress 14/10: no progress 21/10: SH to investigate
061	Refactor dfdl:textNumberFormat to remove dfdl:numberBase. 14/10: Base 2, 8, 16 numbers are invariably integers without formatting, use of pattern etc is overkill 21/10: no progress
062	SH investigate technical writer support.

Closed actions:

054

ICU DecimalNumber/ Calendar behaviour 15/07: No progress 29/07: No Progress. 05/08: No Progress. This action is to discover and document ICU behaviour. DFDL will do whatever ICU does. 12/08: No Progress 19/09: More examples of inconsistent behaviour discovered 09/09: no progress 16/09: no progress 30/09: no progress 07/10: no progress 14/10: no progress 21/10: Decided to list the know issues and combine with action 012 .Closed

Work items:

No	Item	target version	status
005	Improvements on property descriptions		not started
011	How speculative parsing works (combining choice and variable-occurence - currently these are separate) (from action 045)		awaiting completion of actions 045
012	Reordering the properties discussion: move representation earlier, improve flow of topics		not started
033	Numeric data - what physical reps are allowed for what logical types (from action 020)	037	ensure all behaviour documented
036	Update dfdl schema with change properties	ongoing
038	Improve length section including bit handling		some improvement in 036
042	Mapping of the DFDL infoset to XDM	none	not required for V1 specification
051	Revised scoping rules (from action 051)	037	awaiting completion of action 051
058	textPadCharacter %#rxx limitation and split to textxxxxPadCharacter	037
059	limit terminatorCanBeMissing to last element in schema. Ignore elsewhere.	037
060	New empty string semantic for dfdl:binaryBooleanTrueRep	037
061	Change maxOccurs violations from processing error to validation error (if not 'fixed')	037

ã Copyright IBM Corp. 1998, 2007 All Rights Reserved

Alan Powell

MP 211, IBM UK Labs, Hursley,  Winchester, SO21 2JN, England
Notes Id: Alan Powell/UK/IBM     email: alan_powell@uk.ibm.com  
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