See also: IRC log
<ChrisW> Meeting: RIF Telecon 15 Jan 2008
<ChrisW> Scribe: Gary Hallmark
<ChrisW> EtnaRosso, who are you?
<EtnaRosso> hi ChrisW
<EtnaRosso> should i go? i'm not involved in rif
<EtnaRosso> ok have a good meeting
<scribe> Scribe: Gary Hallmark
<scribe> ScribeNick: GaryHallmark
<ChrisW> anyone on IRC who is not on the phone???
<PaulaP> I am not on the phone yet
<ChrisW> Minutes of Jan 8 Telecon
<ChrisW> RESOLVED: Accept Jan 8 Telecon minutes
<csma> @Axel, Zakim is not with us, that's why...
<csma> ...he got to excited and had to leave...
josb: owl DL and owl Full have incompatible RIF mappings
<Harold> Did the OWL WG look into the RIF builtin proposal?
<csma> ack ??P29
harold: RIF uses functions as operators, what does owl do?
josb: mathML is being discussed, more on Friday
<ChrisW> ack ??
<csma> PROPOSED: to close issue 47 without action (i.e. equality stays in BLD as it is currently specified)
chrisw: last week, nobody objected
<DaveReynolds> I'll abstain
<csma> RESOLVED: to close issue 47 without action (i.e. equality stays in BLD as it is currently specified)
<ChrisW> Abstentions: Hassan (Ilog), DaveR (HP)
<ChrisW> ack ??
harold: relational tables map naturally to slotted uniterms
csma: could just agree on
position out of band
... in slotted case, need to agree on table and column names anyway
harold: such a "schema" of DB is needed, but is a different issue
csma: do not need slotted uniterms to avoid OIDs
harold: slot names are
... if frames need slots, why not uniterms?
... slotted uniterms implemented in ojdrew
sandro: any relation of frames to bnodes?
josb: skolemize blank nodes
... but embedding relations is different from RDF
sandro: embedding relational DB
in RDF is common
... should be able to use frames for RDF and relational data
mark: need anonymous or local OID
csma: RIF does not specify an OID format
mark: rule engines don't generate the OID until fact is inserted into engine
<AxelPolleres> Is that relating to set- vs multiset-semantics? i.e. two uniterms with different generated oids are different things (objects), but not if you just see the uniterm... our logical semantics is obviously set-based
<AxelPolleres> jos, I think the discussion is whether we need slotted uniterms, or whether they can (in *any* case) be emulated with oids?
josb: tuple is self-identifying
-- doesn't matter if you use names or positions
... reiterates csma's point
harold: Codd's intent of "tuple" seems to include slots
<josb> columns, not rows!!!!
<josb> not frames, uniterms!!!
chrisw: does converting to frames do anything bad?
axel: tuples can appear > 1 (multiset)
josb: pure relational is set based, SQL is multiset
axel: need OIDs anyway to handle duplicate tuples
harold: what about positional frames?
<AxelPolleres> +1 to what you said now, harold. I didn't speak againt named uniterms.
harold: slots and OIDs are independent, so 4 combinations
<AxelPolleres> ... only against the use case relational databases. Agree, that this is ugly in RDBMS
csma: RIF not meant to interchange DBs
harold: but we are close to datalog and should be useful for such interchange
chrisw: straw poll
<Harold> Gary: yes.
<ChrisW> Who favors keeping named-argument uniterms?
<AxelPolleres> +1 for reasons mentioned in the last telecon, I favor keeping BLD general and we have a clean definition of these already
<ChrisW> Who favors removing named-argument uniterms?
<csma> PROPOSED: BLD WD2 will include the builtins listed in  (functions on numerics),  (functions on strings) and  (functions on dates and times)
<csma> PROPOSED: BLD WD2 will include the builtins listed in http://lists.w3.org/Archives/Public/public-rif-wg/2008Jan/0073.html
<Hassan> I agree
<PaulaP> this list is for BLD, we didn't discuss this issue for Core
dave: status of builtin functions vs. predicates?
<sandro> Sandro: are external calls excluded from core (as Dave seems to be assuming) ?
dave: don't we need predicates if
we don't have equality (talking about Core)
... functions w/o equality makes it hard to return a computed value in an answer
<Harold> Sandro, I dont remember a decision; I think we do need external calls (builtins, fcts or preds) in the Core.
csma: PRD prefers builtin fcns over preds
<PaulaP> we have functions and operators in the list
<sandro> Harold, I agree we want builtins --- I'm just not sure if they might be function-style.
<Harold> Well, only today we decided to keep equality...
<Harold> ... which is needed to call function-style.
<AxelPolleres> add(X,Y,Z) it wouldn't bind a value to Z, but it would have aa fixed interpretation which allows only one value for Z if X and Y are bound.
<AxelPolleres> ... slight difference.
dave: w/o equality in Core, functional style builtins are less useful than predicate style
<Harold> Equality with builtin calls on right-hand side corresponds to Prolog's "is" primitive.
dave: what about list
... need to agree on specifics of the list type for next draft
... need to specify collation
<PaulaP> e.g contains
dave: e.g. compare builtin
... minimum is simple codepoint collation
... or just omit colation sensitive builtins altogether
josb: can't decide on list of builtins before deciding on functional vs. predicate style
<csma> Arghhh! The proposed resolution has been implicitely or explicitely on the table for a long long time!
<scribe> ACTION: daver to add collation issue to builtins wiki page [recorded in http://www.w3.org/2008/01/15-rif-minutes.html#action01]
<trackbot-ng> Sorry, couldn't find user - daver
<scribe> ACTION: davereynolds to add collation issue to builtins wiki page [recorded in http://www.w3.org/2008/01/15-rif-minutes.html#action02]
<trackbot-ng> Sorry, couldn't find user - davereynolds
<scribe> ACTION: dreynolds2 to add collation issue to builtins wiki page [recorded in http://www.w3.org/2008/01/15-rif-minutes.html#action03]
<trackbot-ng> Sorry, couldn't find user - dreynolds2
<scribe> ACTION: dreynold2 to add collation issue to builtins wiki page [recorded in http://www.w3.org/2008/01/15-rif-minutes.html#action04]
<trackbot-ng> Created ACTION-400 - Add collation issue to builtins wiki page [on Dave Reynolds - due 2008-01-22].
josb: also need to define
semantics of builtins
... before we can evaluate the proposed list of builtins
<AxelPolleres> I think, so far, we only have sketched/discussed the semantics for built-on *predicates*, AFAIK
josb: model theoretic RIF semantics w.r.t. builtins
josb: need semantics of "ExtTerm"
<AxelPolleres> We diden't fix how ExtTerms look like though (BTW), did we? We just said we want them to be syntacticcally distinguisheable
chrisw: same semantics as "Term"
josb: but there are outstanding issues w.r.t. Error handling
<Harold> We seem not to know yet if Equality should be allowed both in BLD and in Core, but I think we will need builtins in Core. So in order to allow the more natural functional builtins in Core we should allow (restricted) Equality there.
chrisw: not ready for resolution
chrisw: the issue is about lists
<AxelPolleres> +1 to jos, nothing to add, we need to have the semantics of built-in preds and functions on the table, then we can discuss it. Agree that it should be straightfwd for most predicates, not sure about functions at the moment, but hopefully similar
<DougL> I think we should have both, don't you think?
<josb> -1 to have both
<AxelPolleres> as for the tagnames, should we use ones more similar to the resp. rdf vocabulary, i.e. List, first, rest, nil instead of Pair
harold: alternatives are pairs
vs. n-ary sequences
... n-ary sequences are more common
<DougL> I meant for conceptual impedance matching, allowing both, not saving a few bits. What is the COST of allowing both?
<AxelPolleres> rdf doesn't have seq ... prolog doesn't have seq
chrisw: anyone really want pairs?
<AxelPolleres> they use the pair stuff, but Prolog has syntactic sugar for something which looks like seqs.
<Harold> Axel, prolog has seq's [e1, e2, ..., eN].
<AxelPolleres> I see the point with the blowup in the xml though...
chrisw: pairs take a lot of space to represent in xml
<DougL> These are arguments for allowing sequences; they are not arguments for NOT having pairs as well.
hassan: not completely equivalent in non-ground case
<DougL> that sounds good to me (whoever is saying that)
<DaveReynolds> +1 to Jos
<Hassan> +1 with Jos
<csma> @Doug: it is Jos De Bruijn
<DougL> +2 Jos then
josb: use pairs in language defn, sequences in xml
<DougL> (+2 means: I not only agree, I wish I had said that)
<AxelPolleres> 0 why have syntactic sugar in the XML and not in the presentation syntax?
chrisw: straw poll on Jos's statement
<josb> axel: sequences cannot be incomplete, as Hassan mentioned
axel: but language defn should be readable, therefore use sequences
<IgorMozetic> +1 for Axel
axel: don't read xml, don't care about xml syntax
<josb> fine with me as well
<Hassan> fine here too
axel: semantics uses pairs,
presentation syntax and xml syntax uses sequences
... prefer 1b for semantics, 1a for syntax
<josb> Seq ( a ?Y c | ?R) as shortcut?
axel: 1a, 1b from http://www.w3.org/2005/rules/wg/wiki/Core/List_Constructor
chrisw: let's resolve next week
<AxelPolleres> jos? didn't get your example.
harold: which wiki are we supposed to use?
<AxelPolleres> ... what does the pipe there?
<ChrisW> Paula, can you scribe next week?
<josb> we need to distinguish between last element and tail
<josb> after | is the tail (see bottom of page)
<AxelPolleres> I wouldn't allow '|' in Seq
sandro: wants feedback on conversion of docs to new wiki
sandro: new wiki can allow wiki editing and html editing
<Hassan> Sorry gotta go... Bye...
<AxelPolleres> but use Seq ( a b c) as a shortcut for rif:list( rif:frst (a) rif:rest( rif:list(rif:irst(b) rif:rest( rif:List( rif:first(c) rif:rest(rif:nil) ) ) )
<ChrisW> d'oh again
This is scribe.perl Revision: 1.128 of Date: 2007/02/23 21:38:13 Check for newer version at http://dev.w3.org/cvsweb/~checkout~/2002/scribe/ Guessing input format: RRSAgent_Text_Format (score 1.00) Succeeded: s/st-/set-/ Succeeded: s/to/over/ Succeeded: s/wrt/w.r.t./ Found Scribe: Gary Hallmark Found Scribe: Gary Hallmark Found ScribeNick: GaryHallmark Default Present: Hassan_Ait-Kaci, Gary_Hallmark, +39.047.1.aaaa, Stella_Mitchell, ChrisW, PaulaP, josb, csma, IgorMozetic, Sandro, Harold, DaveReynolds, AxelPolleres, +1.512.342.aabb, DougL Present: Sandro (not on IRC) Regrets: MichaelKifer LeoraMorgenstern PaulVincent Agenda: http://lists.w3.org/Archives/Public/public-rif-wg/2008Jan/0067.html Got date from IRC log name: 15 Jan 2008 Guessing minutes URL: http://www.w3.org/2008/01/15-rif-minutes.html People with action items: daver davereynolds dreynold2 dreynolds2[End of scribe.perl diagnostic output]