- From: Chris Welty <cawelty@frontiernet.net>
- Date: Wed, 15 Nov 2006 00:47:20 -0500
- To: Michael Kifer <kifer@cs.sunysb.edu>
- CC: public-rif-wg@w3.org
Michael Kifer wrote: >> Michael Kifer wrote: >> >>>> Michael Kifer wrote: >>>> >>>> >>>>>>> I find the formulation >>>>>>> >>>>>>> Implies >>>>>>> head: LitForm >>>>>>> body: Condit >>>>>>> >>>>>>> makes it much more clear that "head" and "body" name the roles that the >>>>>>> parts of the implication statement play. >>>>>>> >>>>>>> >>>>>>> >>>>>> Ah; that's a good illustration. >>>>>> >>>>>> Like Michael (13 Nov 2006 20:21:21 +0100) I'm happy to use turtle, >>>>>> I'm beginning to see your point. >>>>>> >>>>>> >>>>>> >>>>> I am not against a frame notation like the above. But in my view this has >>>>> to do with an ontology of rule parts rather than with the syntax. >>>>> When we do XML syntax I don't think it is useful to get out of our way to >>>>> emphasize that the head and the body can come in any order. In fact, this >>>>> is useless and harmful, IMO. >>>>> >>>>> >>>>> >>>> Michael, >>>> >>>> To paraphrase your own message of 11/11, >>>> >>>> Can you please formulate what exactly is the problem using more concrete terms? >>>> What is the problem with asn06 syntax that Sandro has used and how does BNF resolve that? >>>> >>>> I do not understand your objection nor your use of the terms "useless" and "harmful" here. >>>> >>>> >>> The attribution of "useless" and "harmful" is very clear in the above, and >>> it doesn't refer to Sandro's proposal as such. >>> The "useless" and "harmful" refers to going out of the way to ensure that >>> XML syntax doesn't order the terms. >>> >>> >> OK, then you haven't understood the proposal. It is not about ordering, >> > > I think I did understand. Ordering was one and the only issue that was > mentioned as an advantage. > ? Not sure what you are trying to achieve here. The main issue/advantage is role naming. >> it is about identifying the role something plays in a piece of syntax. >> Imagine a language (like FOL) where the head and body of the rule have >> the same syntax, in BNF you would have something like: >> >> Rule: <expr> :- <expr> >> > > How about: > > Rule ::= Head :- Body > Head ::= expr > Body ::= expr > > You can achieve the part-naming effect with BNF in this way. > This is like suggesting using a class instead of a relation. With this approach you cannot reuse the notion of "being a" head or body. If some other part of the grammer needs roles like head and body, they are stuck being <expr>. With an abstract syntax, I distinguish between these "role names" and the productions. The role names are just that: names for the role a particular part of a production plays. Anyway, in the telecon today we agreed to let the two syntaxes, since they are isomorphic, live side by side and after we see some more examples of how it's used we can decide as a group. The only substantive objection to ASNs that I heard today was their relative unfamiliarity compared to BNF. >>> Regarding the "problem", which I see, I also explained it in a previous >>> message: Our progress is slow because we are getting side-tracked by >>> tertiary issues. >>> >> There are many reasons why our progress has been slow. But this issue >> is primary, so let's get it out of the way so we can get to the next one. >> > > I don't think that the choice of notation for specifying the syntax is even > a secondary issue. > If you truly think its unimportant, then you probably shouldn't prolong the discussion (this was advice I received upon getting married). -Chris -- Dr. Christopher A. Welty IBM Watson Research Center +1.914.784.7055 19 Skyline Dr. cawelty@frontiernet.net Hawthorne, NY 10532 http://www.research.ibm.com/people/w/welty
Received on Wednesday, 15 November 2006 05:48:47 UTC