相关疑难解决方法(0)

我正在创建一个非常简单的规则语言的正式规范,非常简单.我想使用EBNF,因为这是一个标准,但我无法弄清楚如何指定操作顺序.到目前为止,这是规范.

rule = statement, { (‘AND’|’OR’), statement};

variable = ‘$’,alphabetic character, {alphabetic character | digit};

statement = variable, [ ‘count’,[white space ],’>’,[white space],number ];

alphabetic character = "A" | "B" | "C" | "D" | "E" | "F" | "G"
                     | "H" | "I" | "J" | "K" | "L" | "M" | "N"
                     | "O" | "P" | "Q" | "R" | "S" | "T" | "U"
                     | "V" | "W" | "X" | "Y" | "Z" ;

number …