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|
%{
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "expr.h"
#include "y.tab.h"
extern int yylex(void);
extern int yyerror(const char *s);
static void breakpoint(void) { }
static void expr_only_integers(YYSTYPE *y1, YYSTYPE *y2)
{
if (y1->type == STRING) {
fprintf(stderr, "expr: %s is not an integer\n", y1->u.s);
exit(1);
}
if (y2->type == STRING) {
fprintf(stderr, "expr: %s is not an integer\n", y2->u.s);
exit(1);
}
}
static int expr_compare(YYSTYPE *y1, YYSTYPE *y2)
{
if (y1->type == INTEGER && y2->type == INTEGER) {
return y1->u.i - y2->u.i;
}
char buf[64];
char *s1 = y1->u.s;
char *s2 = y2->u.s;
if (y1->type == INTEGER) {
snprintf(buf, sizeof(buf), "%d", y1->u.i);
s1 = buf;
} else if (y2->type == INTEGER) {
snprintf(buf, sizeof(buf), "%d", y2->u.i);
s2 = buf;
}
return strcmp(s1, s2);
}
%}
%token INTEGER
%token STRING
%token '(' ')'
%left ':'
%left '*' '/' '%'
%left '+' '-'
%left '=' '<' '>' LE GE NE
%left '&'
%left '|'
%start expr
%%
expr : STRING {
}
| INTEGER {
}
| '(' expr ')' {
}
| expr ':' expr {
printf("match\n");
}
| expr '*' expr {
expr_only_integers(&$1, &$3);
$$.u.i = $1.u.i * $3.u.i;
printf("%d\n", $$.u.i);
}
| expr '/' expr {
expr_only_integers(&$1, &$3);
$$.u.i = $1.u.i / $3.u.i;
printf("%d\n", $$.u.i);
}
| expr '%' expr {
expr_only_integers(&$1, &$3);
$$.u.i = $1.u.i % $3.u.i;
printf("%d\n", $$.u.i);
}
| expr '+' expr {
expr_only_integers(&$1, &$3);
$$.u.i = $1.u.i + $3.u.i;
printf("%d\n", $$.u.i);
}
| expr '-' expr {
expr_only_integers(&$1, &$3);
$$.u.i = $1.u.i - $3.u.i;
printf("%d\n", $$.u.i);
}
| expr '=' expr {
int r = expr_compare(&$1, &$3) == 0;
printf("%d\n", r);
}
| expr NE expr {
int r = expr_compare(&$1, &$3) != 0;
printf("%d\n", r);
}
| expr '<' expr {
int r = expr_compare(&$1, &$3) < 0;
printf("%d\n", r);
}
| expr LE expr {
int r = expr_compare(&$1, &$3) <= 0;
printf("%d\n", r);
}
| expr '>' expr {
int r = expr_compare(&$1, &$3) > 0;
printf("%d\n", r);
}
| expr GE expr {
int r = expr_compare(&$1, &$3) >= 0;
printf("%d\n", r);
}
| expr '&' expr {
printf("and\n");
}
| expr '|' expr {
printf("or\n");
}
;
|
