unrecognized rule in lex
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by Max
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Published on 2010-04-25T01:40:05Z
Indexed on
2010/04/25
1:43 UTC
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Hit count: 386
lex
I'm writing a program in lex, and it gives me the following error:
scanner.l:49: unrecognized rule
Line 49 is: {number} {return(NUM);}
Here's my code:
#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} | _)*
number {digit}+
%%
{ws} {/* no action and no return */}
[\n] {line++;}
bool {return(BOOL);}
else {return(ELSE);}
if {return(IF);}
true {return(TRUE);}
while {return(WHILE);}
do {return(DO);}
false {return(FALSE);}
int {return(INT);}
void {return(VOID);}
{id} {return(ID);}
{number} {return(NUM);} // error is here
"(" {yylval = LPAREN; return(PUNCT);}
")" {yylval = RPAREN; return(PUNCT);}
"[" {yylval = LBRACK; return(PUNCT);}
"]" {yylval = RBRACK; return(PUNCT);}
"{" {yylval = LBRACE; return(PUNCT);}
"}" {yylval = RBRACE; return(PUNCT);}
";" {yylval = SEMI; return(PUNCT);}
"," {yylval = COMMA; return(PUNCT);}
"+" {yylval = PLUS; return(OP);}
"-" {yylval = MINUS; return(OP);}
"*" {yylval = TIMES; return(OP);}
"/" {yylval = DIV; return(OP);}
"%" {yylval = MOD; return(OP);}
"&" {yylval = ADDR; return(OP);}
"&&" {yylval = AND; return(OP);}
"||" {yylval = OR; return(OP);}
"!" {yylval = NOT; return(OP);}
"!=" {yylval = NE; return(OP);}
"=" {yylval = IS; return(OP);}
"==" {yylval = EQ; return(OP);}
"<" {yylval = LT; return(OP);}
"<=" {yylval = LE; return(OP);}
">" {yylval = GT; return(OP);}
">=" {yylval = GE; return(OP);}
%%
What is wrong with that rule? Thanks.
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