At 23:13 1/10/2009, Naveen Chawla wrote: > complement: indirectObject? object; > > indirectObject : nounPhrase; > > object : nounPhrase; > > nounPhrase : 'the' adjectivePhrase? 'noun'; > > adjectivePhrase : '<Ving>' complement?; > >gives > >"error(211): predicate.g:7:14: [fatal] rule complement has >non-LL(*) decision due to recursive rule invocations reachable >from alts 1,2. Resolve by left-factoring or using syntactic >predicates or using backtrack=true option."
The problem with this is that at the left edge of complement, it needs to evaluate whether indirectObject is present or not. To do that, it attempts to match a nounPhrase, which will attempt to match an adjectivePhrase, which brings it right back to the left edge of complement -- and since that's optional too, it has to continue scanning forward into a death spiral. As written here, you should be able to fix it by switching the optionality in the complement rule: complement: object object?; I suspect that in your real grammar the indirectObject and object rules aren't actually equivalent though, so this may not help much. :) List: http://www.antlr.org/mailman/listinfo/antlr-interest Unsubscribe: http://www.antlr.org/mailman/options/antlr-interest/your-email-address --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "il-antlr-interest" group. To post to this group, send email to il-antlr-interest@googlegroups.com To unsubscribe from this group, send email to il-antlr-interest+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/il-antlr-interest?hl=en -~----------~----~----~----~------~----~------~--~---
