/* Written by Pace Willisson (pace@blitz.com)
* and placed in the public domain.
* Largely rewritten by J.T. Conklin (jtc@wimsey.com)
* $Id : /b/source/CVS/src/bin/expr/expr.y,v 1.11 1993/08/17 16:01:23 jtc Exp $
%left <val> '=' '>' '<' GE LE NE
start: expr { result = $$; }
| '(' expr ')' { $$ = $2; }
| expr '|' expr { $$ = op_or ($1, $3); }
| expr '&' expr { $$ = op_and ($1, $3); }
| expr '=' expr { $$ = op_eq ($1, $3); }
| expr '>' expr { $$ = op_gt ($1, $3); }
| expr '<' expr { $$ = op_lt ($1, $3); }
| expr GE expr { $$ = op_ge ($1, $3); }
| expr LE expr { $$ = op_le ($1, $3); }
| expr NE expr { $$ = op_ne ($1, $3); }
| expr '+' expr { $$ = op_plus ($1, $3); }
| expr '-' expr { $$ = op_minus ($1, $3); }
| expr '*' expr { $$ = op_times ($1, $3); }
| expr '/' expr { $$ = op_div ($1, $3); }
| expr '%' expr { $$ = op_rem ($1, $3); }
| expr ':' expr { $$ = op_colon ($1, $3); }
vp = (struct val *) malloc (sizeof (*vp));
vp = (struct val *) malloc (sizeof (*vp));
if (vp == NULL || ((vp->u.s = strdup (s)) == NULL)) {
sprintf (tmp, "%d", vp->u.i);
return (vp->type == string);
if (strchr ("|&=<>+-*/%:()", *p))
} else if (strlen (p) == 2 && p[1] == '=') {
yylval.val = make_str (p);
if (vp->type == integer) {
return (*vp->u.s == 0 || (to_integer (vp) && vp->u.i == 0));
if (result->type == integer)
printf ("%d\n", result->u.i);
printf ("%s\n", result->u.s);
exit (is_zero_or_null (result));
errx (2, "syntax error");
if (is_zero_or_null (a)) {
if (is_zero_or_null (a) || is_zero_or_null (b)) {
return (make_integer (0));
if (isstring (a) || isstring (b)) {
r = make_integer (strcoll (a->u.s, b->u.s) == 0);
r = make_integer (a->u.i == b->u.i);
if (isstring (a) || isstring (b)) {
r = make_integer (strcoll (a->u.s, b->u.s) > 0);
r= make_integer (a->u.i > b->u.i);
if (isstring (a) || isstring (b)) {
r = make_integer (strcoll (a->u.s, b->u.s) < 0);
r = make_integer (a->u.i < b->u.i);
if (isstring (a) || isstring (b)) {
r = make_integer (strcoll (a->u.s, b->u.s) >= 0);
r = make_integer (a->u.i >= b->u.i);
if (isstring (a) || isstring (b)) {
r = make_integer (strcoll (a->u.s, b->u.s) <= 0);
r = make_integer (a->u.i <= b->u.i);
if (isstring (a) || isstring (b)) {
r = make_integer (strcoll (a->u.s, b->u.s) != 0);
r = make_integer (a->u.i != b->u.i);
if (!to_integer (a) || !to_integer (b)) {
errx (2, "non-numeric argument");
r = make_integer (a->u.i + b->u.i);
if (!to_integer (a) || !to_integer (b)) {
errx (2, "non-numeric argument");
r = make_integer (a->u.i - b->u.i);
if (!to_integer (a) || !to_integer (b)) {
errx (2, "non-numeric argument");
r = make_integer (a->u.i * b->u.i);
if (!to_integer (a) || !to_integer (b)) {
errx (2, "non-numeric argument");
errx (2, "division by zero");
r = make_integer (a->u.i / b->u.i);
if (!to_integer (a) || !to_integer (b)) {
errx (2, "non-numeric argument");
errx (2, "division by zero");
r = make_integer (a->u.i % b->u.i);
/* coerce to both arguments to strings */
/* compile regular expression */
if ((eval = regcomp (&rp, b->u.s, 0)) != 0) {
regerror (eval, &rp, errbuf, sizeof(errbuf));
/* compare string against pattern */
/* remember that patterns are anchored to the beginning of the line */
if (regexec(&rp, a->u.s, 2, rm, 0) == 0 && rm[0].rm_so == 0) {
*(a->u.s + rm[1].rm_eo) = '\0';
v = make_str (a->u.s + rm[1].rm_so);
v = make_integer (rm[0].rm_eo - rm[0].rm_so);
/* free arguments and pattern buffer */