LR Parsers Advantages: (1) LR parsers can be constructed to recognize all programming language construct for which context-free grammars can be written. (2) The LR parsing method is more general and efficient than other shift-reduce technique. (3) The class of grammars that can be parsed by LR parser is the proper superset of the class of grammars that can be parsed by predictive parsers. (4) LR parsers can detect errors in syntax as soon as possible