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#include "expr.h"

// Custom function that returns the sum of its two arguments
static float add(struct expr_func *f, vec_expr_t args, void *c) {
  float a = expr_eval(&vec_nth(&args, 0));
  float b = expr_eval(&vec_nth(&args, 1));
  return a + b;
}

static struct expr_func user_funcs[] = {
	{"add", add, 0},
	{NULL, NULL, 0},
};

int main() {
	char* a = (char*)malloc(40);
	const char *s = "x = 5, add(2, x)";
  struct expr_var_list vars = {0};
  struct expr *e = expr_create(s, strlen(s), &vars, user_funcs);
  if (e == NULL) {
    printf("Syntax error");
		return 1;
	}

	float result = expr_eval(e);
	printf("result: %f\n", result);

	expr_destroy(e, &vars);
	return 0;
}

CFLAGS:= -Wfatal-errors -pedantic -Wall -Wextra -Werror -std=c99