7.2 LR Parsing

• LR parsers recognize the same languages as deterministic pushdown automata
• LR parsers use LR-items to remember
  1. Candidate production rules to be used in reductions
  2. Current positions within the candidate rules
• The LR-items are recorded in the pushdown memory, instead of recording just nonterminal and terminal symbols.
• Each LR-item stands for a nonterminal or terminal symbol and the context in which the symbol may appear