Info.ReductionSourceReduction information. A reduction represents a (state, production, lookahead set) triple, meaning that in the given state, when the lookahead terminal is in the set, the parser should reduce by the given production.
state r returns the LR(1) state where reduction r applies
production r returns the production that reduction r reduces by
lookaheads r returns the set of lookahead terminals for reduction r. When the next input terminal is in this set, the reduction is triggered.
from_lr1 g s returns the set of all reductions applicable in LR(1) state s