string get_stack() {
    int i, s;
    string list = "";
    string *stack0 = call_stack(0);
    string *stack1 = call_stack(1);
    string *stack2 = call_stack(2);
    //tc("sizeof(stack1): "+sizeof(stack1));
    for(i = 0, s = sizeof(stack1); i < s; i++){
	list +="\n"+i+":"+identify(stack2[i])+"."+identify(stack1[i])+"."+identify(stack2[i]);
	//list = implode(stack," ");
    }
    return list;
}