我正在用lex编写一个程序,它给了我以下错误:
scanner.:49:无法识别的规则
第49行是: {number} {return(NUM);}
编辑:但是,错误似乎与之前的行直接相关{id} {return(ID);}.它将在该规则之后直接列出该行作为错误的来源,即使它是空白的.
这是我的代码:
#include <stdio.h>
%token BOOL, ELSE, IF, TRUE, WHILE, DO, FALSE, INT, VOID
%token LPAREN, RPAREN, LBRACK, RBRACK, LBRACE, RBRACE, SEMI, COMMA, PLUS, MINUS, TIMES
%token DIV, MOD, AND, OR, NOT, IS, ADDR, EQ, NE, LT, GT, LE, GE
%token NUM, ID, PUNCT, OP
int line = 1, numAttr;
char *strAttr;
%}
/* regular definitions */
delim [ \t]
ws {delim}+
letter [A-Za-z]
digit [0-9]
id ({letter} | _)({letter} | {digit} …Run Code Online (Sandbox Code Playgroud) lex ×1