precedence grammar

• 优先文法

precedence grammar的用法和样例：

例句

1. The new grammar is unambiguous and an efficient parsing algorithm is also given.
   不包含单项产生式的运算符优先文法也是它的真子文法。
2. Therefore the class of generalized precedence grammar is a superclass of the weak precedence grammar.
   弱优先文法和弱运算符优先文法都是它的真子文法。