DFDL: Minutes of call 2007-10-24T12:00-04:00 (EDT.US)

Mike Beckerle
Simon Parker
Steve Hanson
Alan Powell

Topics:
- infoset proposal described. To be circulated asap by Steve for feedback particularly from Simon.
- facets doc and null/optional/default doc

Highlights:

- approach re: strict min/max occurs interpretation and optional vs. required generally seems to have consensus.
- ok with restrictions that unordered sequences and 'suppress' separators ordered sequences must have initiators specified.
- nested variable length arrays inside sequences using the same delimiter must be allowed so long as the syntax is unambiguous.

- we decided to reconsider whether groups (sequence or choice) should be allowed to carry max/min occurs. This introduces some infoset issues (how do you discuss the 2nd child of the 2nd anonymous sequence of an element - XML Infoset and even XML PSVI say you can't. We need to be able to.).  There are substantial benefits to allowing this min/max occurs in that it lets us express the semantics of many properties with compact examples of equivalent DFDL.  We expect these advantages to carry over also into user format specifications.

- additional comments on these docs are sought asap so as to have them before reintegrating this into the main spec.

Mike Beckerle
STSM, Architect, Scalable Computing
IBM Software Group
Information Platform and Solutions
Westborough, MA 01581
direct: voice and FAX 508-599-7148
assistant: Pam Riordan  
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