The traditional LALR analysis is reexamined using a new operator and an associated graph. An improved method that allows factoring out a crucial part of the computation for defining states of LR(0) canonical collection and for computing LALR(1) lookahead sets is presented. This factorization leads to significantly improved algorithms with respect to… (More)
We have read with more than a passing interest a recent paper by Fred Ives [ 1 ] dealing with algorithms for computing LALR(I) lookahead sets. In the paper a claim is made that our algorithm published earlier in Park et al. has been improved. One purpose of this note is to raise questions about this claim. After trivial changes in notation, such as… (More)
A new formalism pertaining to LALR analysis is described which serves the dual purpose of providing efficient algorithms and of facilitating their correctness proofs.