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A simple precedence grammar is a context-free formal grammar that can be parsed with a simple precedence parser.〔 The Theory of Parsing, Translation, and Compiling: Compiling, Alfred V. Aho, Jeffrey D. Ullman, Prentice–Hall, 1972.〕 The concept was first developed by Niklaus Wirth and Helmut Weber from the ideas of Robert Floyd in their paper, ''EULER: a generalization of ALGOL, and its formal definition'', in the Communications of the ACM in 1966. ==Formal definition== G = (''N'', Σ, ''P'', ''S'') is a simple precedence grammar if all the production rules in ''P'' comply with the following constraints: * There are no erasing rules (ε-productions) * There are no useless rules (unreachable symbols or unproductive rules) * For each pair of symbols ''X'', ''Y'' (''X'', ''Y'' (''N'' ∪ Σ)) there is only one Wirth–Weber precedence relation. * G is uniquely inversible 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「simple precedence grammar」の詳細全文を読む スポンサード リンク
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