/* OLD SOURCE HANGING AROUND AS AN IMPLEMENATION REFERENCE
 */
OBJ env_reference_symbol (OBJ o) {
 U32 g;
BGRN;DB1("ENV_REFERENCE_SYMBOL ", o);
	g = obj_reference_generation(o);
	while(g--) o = mem_vec_obj(o, 0);
	return mem_vec_obj(mem_vec_obj(o,1), obj_reference_offset(o)-2);
}
void env_reference_value (void) {
 U32 g;
BGRN;DB1("ENV_REFERENCE_VALUE: ", acc);
	g = obj_reference_generation(acc);
	while(g--) env = mem_vec_obj(env, 0);
	acc = mem_vec_obj(env, obj_reference_offset(acc));
GRN;DB1(" returning ", acc);
}

int is_syntatic_keyword (OBJ o) {
 char *c;
BRED;DB1("is_syntatic_keyword: ", o);
	if (!is_symbol(o)) {
BRED;DB(" not a symbol: ");
		return 0;
	}
	c = obj_symbol(o);
BRED;DB(" switching...");
	switch (*c++) {
		case 'a' : return strcmp(c, "nd")?0:syn_and;
		case 'b' : return !strcmp(c, "egin");
		case 'd' : return !strcmp(c, "efine");
		case 'i' : return *c=='f';
		case 'l' : return !strcmp(c, "ambda") || !strcmp(c, "et");
		case 'o' : return *c=='r';
		case 'q' : return !strcmp(c, "uasiquote") || !strcmp(c, "uote");
		case 's' : return !strncmp(c, "et!", 3);
		case 'u' : return !strcmp(c, "nquote");
		default : return 0;
	}
}

#ifdef 0
void op_quasiquote (void) { /* THIS IS ONE DAMN ELEGANT QUASIQUOTE XLATOR */
BCYN;DB1("OP_QUASIQUOTE ", acc); CYN;DB1(" ", stack);
	env=pop();
	r4=pop(); /* LEVEL */
	r3=pop(); /* EXP */
	r2=pop(); /* RESULT OF CDR */
	if (acc)
		if (r2) { /* DONE WITH CAR AND CDR SO CONS AND RETURN */
			push(acc); push(r2); new_pair();
		} else { /* DONE WITH CDR, NOW COMPUTE CAR */
			push(acc); push(0); push(r4); push(env); push(oquasiquote);
			push(0); push(r3); push(r4); push(env); push(oquasiquote);acc=0;
		}
	else
		if (is_pair(r3)) { /* RECURSE CAR AND CDR */
			if (is_symbol(r5=car(r3)))     /* CHECK FOR ANOTHER ` or , */
				if (!strncmp(obj_symbol(r5), "quasiquote", 10)) {
					new_number(obj_number(r4)+1); r4=acc;
				} else if (!strncmp(obj_symbol(r5),"unquote",7))
					if (!obj_number(r4)) {
						push(env); push(oeval); acc=cdr(r3);
						return;
					} else {
						new_number(obj_number(r4)-1); r4=acc;
					}
			push(0); push(car(r3)); push(r4); push(env); push(oquasiquote);
			push(0); push(cdr(r3)); push(r4); push(env); push(oquasiquote);acc=0;
		} else acc=r3; /* RETURN PLAIN OLD ATOM */
}
void syntax_quasiquote (void) {
BRED;DB1(" SYNTAX_QUASIQUOTE: ", acc);
	env=pop();
	push(0); push(car(acc)); new_number(0); push(acc); push(env); push(oquasiquote); acc=0;
}
#endif