Phone Conference P1450.1 Working Doc Subgroup
Thurs May 8, 10:00 am PST
Attendees:
Documents
Agenda
1. WFCConstant proposal (changes-5.8.03.pdf)
2. Fail data (Jason status update)
3. Lockstep (see link above for proposal by Paul Reuter)
Note to 1450.1: This is a proposal that has come from the 1450.6 (CTL)
working group.
Meeting discussion
1. WFCConstant proposal
Reviewed the proposed changes created by Tony, to replace enums by
IntegerConstants.
The one previous behavior that does not have a close parallel is the
"values" attribute. For enumerated variables the values provide the
definition of the permissable values of this variable. The "values"
functionality can be provided, but validation of these values needs to
be performed at run-time, and this group sees little benefit and large
overhead to supporting this construct. The Working Group agreed to
removing the "values" construct in this environment.
Tony identified an ambiguity in the language, differentiating
constants (or in general, any variable, signal, or group name) from
complicated WFC-lists. Tony presented the additional
backslash-operator \V, which shall be present before any
'variable-namespace-reference' is made, to eliminate this
ambiguity. The Working Group accepted this construct. There was some
discussion that the \W operator may provide the same functionality, to
be reviewed.
There was a short discussion about the context of WFC interpretation
with SignalVariables. Because SignalVariables support Base attributes
and are applied interchangeably with Signals and Groups, the
mechanisms of WFC-assignment and WFC-interpretation as defined in
dot-zero apply to SignalVariables. The dot-one spec needs to make this
clear.
There was some quick review of previous meeting decisions on variable
issues, to identify if there was missing additional constructs or
functionality to define. The one issue identified was the question
about where variables become initialized (or set to their initial
values). In a prior meeting, the need for supporting a mechanism to
maintain a variable's value across multiple PatternBursts was
identified, and a "holdstate" construct was contemplated. After some
additional review, the existing mechanism of scope-based
initialization was considered sufficient without attempting an
exception-style attribute to control this behavior; if a variable
needs to be maintained across multiple PatternBursts, then those
Bursts can (and should) be organized hierarchically, with the top
level of the Burst hierarchy containing the Variables-block reference,
controlling instantiation (and initialization) of these variables for
this entire hierarchical scope.
2. Fail data
Jason was not present, however Bruce identified an interest in this
issue as well and will contact Jason with the hope that some progress
can be made on this issue.
3. LockStep
No progress by Tony or Greg on this; continuing AI.
Meeting adjourned at 10:32 PST.
Next meeting
Next phone meeting May 22
AIs