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An operator precedence grammar is a kind of grammar for formal languages.
Technically, an operator precedence grammar is a context-free grammar that has the property that no production has either an empty right-hand side or two adjacent nonterminals in itsright-hand side. These properties allow precedence relations to bedefined between the terminals of the grammar. A parser that exploits these relations is considerably simpler than more general-purpose parsers such as LALR parsers. Operator-precedence parsers can be constructed for a large class of context-free grammars.