1 Nils, defaults and unparsing   

>From last calls minutes
- It was agreed that on unparsing a simple infoset item with no value will 
be treated the same as missing.  Steve H to check WMB behaviour. Need to 
state in 4.1.2 Infoset that value is optional. "

Something to note. We say that for a simple element infoset item 
[dataValue] has a value (either type compliant or nil) and for a complex 
element infoset item [dataValue] has 'no value'.  Also  we say that for a 
simple element infoset item [children] has 'no value' and for a complex 
element infoset item [children] it may have a value (so it could also have 
'no value').  The implication therefore is that an element infoset item is 
deduced to be simple or complex based on the [dataValue] property.  If we 
let a simple item take 'no value' for [dataValue] as proposed, then there 
is no reliable way to identify an element infoset item as simple or 
complex. 

Is that a problem in practice?  After parsing, all simple items will have 
[dataValue] set.  For items created by some other means, and presumably 
destined for unparsing, you could have an item with neither [dataValue] 
nor [children] set.  We could say (1) that an element infoset item is 
known to be simple or complex only when it is processed by the unparser, 
at which point the item is matched to the DFDL schema and its type 
resolved.  This is what broker's MRM parser does.  Alternatively (2) we 
introduce a simple/complex flag. 

Note that I tried creating an MRM 'infoset' item for a string element but 
just gave a name and no value. The MRM serializer looked at the element, 
matched it to its model, found it was simple, and treated the value as 
NULL which invoked null processing.  The XML serializer also assumed NULL.

Personally I think we should adopt (1) but interpret 'no value' for a 
simple item as nil and not missing. 


2  OGF 29 
Chicago, June 20-22

3 Current Actions
see below


4  zoned numbers clarifications
The specification of the number pattern for zoned numbers is not clear.
A.
Clarification:
When dfdl:textNumberRep is ?zoned? only the pattern for positive numbers 
is used. Only the following pattern characters may be used: 

  '+' MUST BE present at the beginning or end of the pattern to indicate 
whether the leading or trailing digit carries the overpunched sign, if the 
logical type is signed
  '+' MAY BE present at the beginning or end of the pattern to indicate 
whether the leading or trailing digit carries the overpunched sign, if the 
logical type is unsigned 
  'V' MAY BE used  to indicate the location of an implied decimal point 
  '0' indicates the number of required digits (including overpunched). 
  '#' indicates the number optional digits.

B.
Also  textNumberPolicy implies it applies to zoned, but doesn't state what 
zoned behaviour it covers. I think it should be consistent with 
binaryNumberCheckPolicy for packed, and control whether positive punched 
data is accepted or rejected when parsing an unsigned type, and whether 
unpunched data is accepted or rejected when parsing a signed type. 

C.
Finally, several textNumber properties only apply to standard or zoned. We 
could distinguish these by name, which is what we have done elsewhere. So:
- textStandardBase
- textStandardGroupSeparator
- textStandardExponentCharacter
- textStandardInfinityRep
- textStandardNanRep
- textStandardZeroRep
- textZonedSignStyle

Current Actions: 
No
Action 
066
Investigate format for defining test cases 
25/11:IBM to see if it is possible to publish its test case format. 
04/12: no update 
... 
17/02: IBM is willing in principle to publish the test case format and 
some of the test cases. May need some time to build a 'compliance suite' 
24/03: No progress 
03/03: Discussions have been taking place on the subset of tests that will 
be provided. 
10/03: work is progressing 
17/03: work is progressing 
31/03: work is progressing 
14/04: And XML test case format has been defined and is being tested. 
21/04. Schema for TDML defined. Need to define how this and the test cases 
will be made public 
05/05: Work still progressing 
084
Check behaviour of dfdl:inputValueCalc and outputValueCalc. 
14/04: no prorgess 
21/04: no progress 
05/05: no progress 
085
ALL: publicize Public comments phase to ensure a good review.. 
14/04: see minutes 
21/04: Press release, OMG and other standards bodies. 
05/05: Alan and Steve H have contacted other standards bodies. Will ask 
them to add comments on spec 
086
AP: Nils and Defaults during unparsing - update table 
31/03: TK to documetn use cases for parsing 
14/04: Investigate new property to control empty string behaviour. 
21/04: After investigation a new property is not required. New rules 
developed and tables updated. 
Need examples of complexTypes to confirm tables apply. 
Review Nils, defaulting spec section. 
05/05: Discussed defaulting complex elements. Tables updated but need to 
add terminator. 
SH; to confirm WMD behaviour when infoset item has no value on unparsing 
Need to describe defaulting choices. 
088
define semantics of choiceKind 'fixedLength' 
31/03: TK to provide definition of calculable length. 
Investigate  PL/I varchars and Cobol occurs dependingon. 
14/04Tim had distributed a document starting the definition of calculable 
length for the longest choice member. 
Alan had done some investigation of COBOL occurs depending on and when 
used in the working section of a program then the maximum storage was 
reserved but when used in the linkage section the dependent number was 
uses. We need to understand how the WMB COBOL importer deals with ODO. 
21/04: Need to define 'calculable length' and WMB importer ODO behaviour. 
05/05: TK: Still need definition of calculable length. 
SKK: WMB COBOL imported behaviour with ODO 
091
The IBM team had questioned whether timezones should be just UTC+/- offset 
or should GMT and other short time zones be allowed. Alan to investigate


Regards

 
Alan Powell
 
Development - MQSeries, Message Broker, ESB
IBM Software Group, Application and Integration Middleware Software
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