Concepts inEfficient Computation of LALR(1) Look-Ahead Sets
In computer science, an LALR parser or Look-Ahead LR parser is a type of LR parser with small parse tables and the ability to handle more grammars than SLR parsers. As with other types of LR parser, an LALR parser is quite efficient at finding the single correct bottom-up parse in a single left-to-right scan over the input stream, without guesswork or backtracking. The parser is mechanically generated from a formal grammar for the language.
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