Overview
When using an LR parser within some larger program, you can usually ignore all the mathematical details about states, tables, and generators. All of the parsing actions and outputs and their timing can be simply understood by viewing the LR parser as just a shift-reduce parser with some nifty decision method. If the generator tool complains about some parts of your grammar, you may need some understanding of states and the difference between LR and LALR in order to tweak your grammar into an acceptable form. Full understanding of grammar and state analysis algorithms is needed only by the tool implementer and by students of parsing theory courses.
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