Bruce, I think you need to be careful about conflating a grammar as a specification of correct sentences (and correspo0nding parse trees) with a grammar as guiding a particular parser implementation. The importance of grammars satisfying certain properties for LL(1) or LALR parser generation is that they permit creation of the parse tree without backtracking. In this case, I think it's sufficient that the grammar satisfies the former purpose; implementation is a matter for the, er, implementer. #g -- At 13:34 06/12/04 -0500, Bruce Lilly wrote: >On Mon December 6 2004 12:00, Graham Klyne wrote: > > > >Are there any implementations using the ABNF as specified in the draft? > > > > My Haskell implementation [1] is hand-coded, but attempts to follow the > > given syntax very closely. But my approach is top-down, not LALR, so that > > probably doesn't answer your question. > >Thanks for the pointers, but you're right that it doesn't answer >my question. My concern is with the specification of the >grammar, which I believe to be incomplete (and therefore >unimplementable as an LALR parser in a manner which >guarantees interoperability) as there is no specified set of >precedence relationships necessary to resolve the existing >conflicts (ideally, there are no conflicts in a well-designed >grammar). ------------ Graham Klyne For email: http://www.ninebynine.org/#ContactReceived on Tuesday, 7 December 2004 11:35:41 UTC
This archive was generated by hypermail 2.4.0 : Sunday, 10 October 2021 22:17:46 UTC