See also: IRC log
<scribe> scribenick: PaulVincent
<scribe> scribe: PaulVincent
<Hassan> mute me
<csma> next item
CSMA: check if dayofweek and timeofday is OK: any complaints
CK: OK if we keep to 1hr
<csma> next item
CSMA: keep DOWeek and TODay
CK: is this bind - need strawman
<ChanghaiKe> do is left as it is, we use bind instead to bind new variable to a new frame
<scribe> ACTION: GH to propose bind [recorded in http://www.w3.org/2008/10/07-rif-prd-minutes.html#action01]
<Gary> did anybody get a chance to read http://www.w3.org/2005/rules/wiki/PRD#Operational_semantics_of_actions
CSMA: other actions include modify, execute, ...
HAK: assign is finer grained than
assert (cf Java)
... remove and add object in assert/retract is not atomic
GH: assert can also be at the slot level
<csma> (bind ?x object(attr->?x) do(assign ?x value))
<Gary> clarification - assert is only at the slot level
<ChanghaiKe> what does this mean? do we assert a whole object?
<Gary> - or you can assert a predicate
<Gary> all - please look at http://www.w3.org/2005/rules/wiki/PRD#Operational_semantics_of_actions
<csma> Forall ?x (?x#FooBor) If condition then assert(?x[attr->value)
HAK: this is nonstandard notation
<csma> New Var Class
CSMA: proposed to use new for new objects and assert for updates
GH: see PRD spec draft http://www.w3.org/2005/rules/wiki/PRD#Operational_semantics_of_actions
CSMA: aside: looking at doing same for conditions
GH: trying to combine operational and model theory
HAK: this has not been done
before so id of concern
... overloading of assert is dangerous
... PR engines assert objects not predicates
CSMA: assert is for facts (as is retract) in PR engines...
CK: difference between
propositional logic vs object logic
... assert into WM is the whole object - but this could be a bunch of triples in a single transaction
<Hassan> yes CK - this is what I meant by granularity
GH: we don't have any semantics
for object based behavior
... ... need to reuse frames etc from core
Main issue if translating OUT OF PRD ie recombining frames etc into object operations
CSMA: issue is one of serialization to map from objects to frames
HAK: issue is we need to be clear: choice is to assert triples that correspond to obj fields
CSMA: Example: JRules asserts an object with field values: serialized into XML means all values?
HAK: ... yes this is a series of asserts
<ChanghaiKe> JRules asserts an object at once
CSMA: Also need to avoid ambiguity
HAK: why no remove
GH: ... this is retract
CSMA: which was an issue for MK
<Hassan> can you post it?
GH: See example 2.11 in http://www.w3.org/2005/rules/wiki/PRD
<scribe> ACTION: CK to create an assert and assign object from JRules [recorded in http://www.w3.org/2008/10/07-rif-prd-minutes.html#action02]
CSMA: needs to be atomic or not?
HAK: issue is of event in between the assert operations - atomic means its locked for the transaction...
+1 to HAK's concern
<ChanghaiKe> +1 to HAK concern
CSMA: Is there a semantic issue here ie can an engine have an interrupt in an retract-assert vs modify
<ChanghaiKe> I can give an example
GH: does this apply for fine-grain assert/retract
CK: example: truth maintenance system
<ChanghaiKe> if temp > 120 then maintain alarm on network element
CK: if I remove temp then TMS would deduce larm not to be maintained
Of course this is the engine semantics, not the language ...
CSMA: remove value not object - is this still the same?
CK: ... but I can't remove the sensor (ie a.temp)
GH: retract ([predicate|frame|object])
<csma> ?x: Device if ?x[value > 120] then assert(?x[alarm->True])
Do we need to prefix/postfix assert/retract ops with a marker eg external(object operation)
<Hassan> +1 with CK
<csma> ?x: Device if ?x[value > 240] and ?x[alarm->True] then Modify(?x[alarm->critical]
Note to CSMA: we are 5mins to end of call...
CK: paper exists that explains differences ?
<scribe> ACTION: CK to find appropriate paper reference or example [recorded in http://www.w3.org/2008/10/07-rif-prd-minutes.html#action03]
This is scribe.perl Revision: 1.133 of Date: 2008/01/18 18:48:51 Check for newer version at http://dev.w3.org/cvsweb/~checkout~/2002/scribe/ Guessing input format: RRSAgent_Text_Format (score 1.00) Succeeded: s/2.1.1/2.11/ Found ScribeNick: PaulVincent Found Scribe: PaulVincent Inferring ScribeNick: PaulVincent WARNING: No "Topic:" lines found. Default Present: csma, Paul_Vincent, ChanghaiKe, Gary, hassan Present: csma Paul_Vincent ChanghaiKe Gary hassan Agenda: http://lists.w3.org/Archives/Public/public-rif-wg/2008Oct/0005.html Got date from IRC log name: 07 Oct 2008 Guessing minutes URL: http://www.w3.org/2008/10/07-rif-prd-minutes.html People with action items: ck gh WARNING: Input appears to use implicit continuation lines. You may need the "-implicitContinuations" option. WARNING: No "Topic: ..." lines found! Resulting HTML may have an empty (invalid) <ol>...</ol>. Explanation: "Topic: ..." lines are used to indicate the start of new discussion topics or agenda items, such as: <dbooth> Topic: Review of Amy's report[End of scribe.perl diagnostic output]