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#include <string.h>
#include <stdio.h>
#include "types.h"
typedef struct val {
type t;
char *name;
union {
int i;
};
} val;
val *vars[4096];
int varcount = 0;
values *eval(ast *a);
values *getval(ast *a, int index, type t) {
values *tmp;
if (t == INT && a->vals->ts[index] == INT)
return a->vals;
else if ((tmp = eval(a->vals->as[index]))->ts[0] == t)
return tmp;
else
fprintf(stderr, "expected value, but got nothing\n");
}
void checkcount(ast *a, int argc) {
if (a->vals->argc != argc)
fprintf(stderr, "incorrect number of args given!\n");
}
values *eval(ast *a) {
values *v = malloc(sizeof(values));
if (strcmp(a->fname, "print") == 0) {
checkcount(a, 1);
printf("%d\n", getval(a, 0, INT)->is[0]);
return NULL;
}
else if (strcmp(a->fname, "set") == 0) {
checkcount(a, 2);
printf("%d\n", getval(a, 0, INT)->is[0]);
return NULL;
}
else if (strcmp(a->fname, "+") == 0) {
v->is[0] = getval(a, 0, INT)->is[0];
for (int i = 1; i < a->vals->argc; i++)
v->is[0] += getval(a, i, INT)->is[i];
v->ts[0] = INT;
v->argc++;
}
else if (strcmp(a->fname, "-") == 0) {
if (a->vals->argc == 1)
v->is[0] = -getval(a, 0, INT)->is[0];
else {
v->is[0] = getval(a, 0, INT)->is[0];
for (int i = 1; i < a->vals->argc; i++)
v->is[0] -= getval(a, i, INT)->is[i];
}
v->ts[0] = INT;
v->argc++;
}
else if (strcmp(a->fname, "*") == 0) {
v->is[0] = getval(a, 0, INT)->is[0];
for (int i = 1; i < a->vals->argc; i++)
v->is[0] *= getval(a, i, INT)->is[i];
v->ts[0] = INT;
v->argc++;
}
else if (strcmp(a->fname, "/") == 0) {
v->is[0] = getval(a, 0, INT)->is[0];
for (int i = 1; i < a->vals->argc; i++)
v->is[0] /= getval(a, i, INT)->is[i];
v->ts[0] = INT;
v->argc++;
}
else if (strcmp(a->fname, "%") == 0) {
v->is[0] = getval(a, 0, INT)->is[0] % getval(a, 1, INT)->is[1];
v->ts[0] = INT;
v->argc++;
}
return v;
}
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