File: expr.lex

package info (click to toggle)
flex 2.5.31-31sarge1
  • links: PTS
  • area: main
  • in suites: sarge
  • size: 8,048 kB
  • ctags: 1,393
  • sloc: ansic: 13,165; sh: 5,433; lex: 3,244; makefile: 1,369; yacc: 966; awk: 78; cpp: 23; sed: 16
file content (35 lines) | stat: -rw-r--r-- 619 bytes parent folder | download | duplicates (11)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
/*
 * expr.lex : Scanner for a simple
 *            expression parser.
 */

%{
#include "y.tab.h"

%}

%%

[0-9]+     { yylval.val = atol(yytext);
             return(NUMBER);
           }
[0-9]+\.[0-9]+ { 
             sscanf(yytext,"%f",&yylval.val);
             return(NUMBER);
           }
"+"        return(PLUS);
"-"        return(MINUS);
"*"        return(MULT);
"/"        return(DIV);
"^"        return(EXPON);
"("        return(LB);
")"        return(RB);
\n         return(EOL);
[\t ]*     /* throw away whitespace */
.          { yyerror("Illegal character"); 
             return(EOL);
           }
%%