On 17-02-07 06:02 PM, Waldemar Horwat wrote:
Lookahead restrictions fit very well into an LR(1) engine [...] it's directly tied into the generation of the automaton states. Each automaton state contains a collection of possible places in the expansions of grammar rules that the state can represent. Following a terminal symbol T from a state A leads to a state B. A lookahead restriction prevents state B's collection from including expansions that would have been prohibited by the lookahead restriction on T. If that generates an inconsistency (for example, if there are two ways to get to an identical state, one with a lookahead restriction and one without), the grammar validation fails.
So that sounds like you form the closure of state A in the standard way, and then use the lookahead-restriction to limit the transitions out of A (and the items that A contributes to the kernel of B). But it seems to me that forming the closure is also affected by the lookahead-restriction. Is that true in your validator?
-Michael _______________________________________________ es-discuss mailing list es-discuss@mozilla.org https://mail.mozilla.org/listinfo/es-discuss
