- From: Michael Kifer <kifer@cs.sunysb.edu>
- Date: Tue, 20 Mar 2007 12:50:05 -0400
- To: =?ISO-8859-15?Q?Hassan_A=EFt-Kaci?= <hak@ilog.com>
- Cc: W3C RIF WG <public-rif-wg@w3.org>
Hassan, I asked you to *specifically* point to a piece of syntax that is allowable by the current draft and that is ambiguous. thanks --michael > It is inherently ambiguous to define a language where lexical categories > and syntactic categories may have the same form. > > For ex., if predicates, sorts, and constants may be uris, how do you > disambiguate an expression like uri1(uri2,uri3)? If you answer, > "thanks its grammatical position: it appears where a predicate, > constant, etc., is expected", then you haven't written a parser > lately... Indeed, the way to know the what *syntactic* category > is expected is using the *lexical* category of a token. So my > question is, when you read a uri off the input stream, what is > its lexical category? > > If uri is a *lexical* category (like 'variable' starting with a ?, > or 'number' being made of numerical digits), do you return "URI" > or "CONSTANT", or "SORT", what? (This is the lexical level, remember!). > > -hak > -- > Hassan Aït-Kaci > ILOG, Inc. - Product Division R&D > tel/fax: +1 (604) 930-5603 - email: hak @ ilog . com > http://koala.ilog.fr/wiki/bin/view/Main/HassanAitKaci > > > > >
Received on Tuesday, 20 March 2007 17:04:21 UTC