for: (from, to, f) => {
	index: from;
	loop {
		if not(inf(index, to)) break true;
		f(index);
		index <- add(index, 1)
	}
};

array_new: () => {
	r: obj();
	r <- set(r, "len", 0);
	r
};

array_len: (self) => {
	get(self, "len")
};

array_get: (self, index) => {
	get(self, str(index))
};

foreach: (arr, f) => {
	l: array_len(arr);
	for(0, l, (i) => {
		f(array_get(arr, i))
	})
};

array_push: (self, e) => {
	i: array_len(self);
	self <- set(self, str(i), e);

	len: add (i, 1);
	self <- set(self, "len", len);
	self
};

array_pop: (self) => {
	l: array_len(self);
	if eq(l, 0) return false;
	
	i: sub(l, 1);
	e: array_get(self, i);
	self <- set(self, str(i), false);

	rest: array_new();
	foreach(self, (item) => { if not(eq(item, false)) rest <- array_push(rest, item) });

	r: obj();
	r <- set(r, "tail", e);
	r <- set(r, "rest", rest);
	r
};

array_swap: (self, i, j) => {
	i_value: array_get(self, i);
	j_value: array_get(self, j);
	self <- set(self, str(j), i_value);
	self <- set(self, str(i), j_value);
	self
};

array_sort: (self, cmp) => {
	l: array_len(self);
	for(0, sub(l, 1), (i) => {
		i_min: i;
		for(add(i, 1), l, (j) => {
			e_j: array_get(self, j);
			e_min: array_get(self, i_min);
			if inf(cmp(e_j, e_min), 0) i_min <- j
		});
		self <- array_swap(self, i, i_min)
	});
	self
};

array_print: (self) => {
	l: array_len(self);
	r: "[ ";
	for(0, l, (i) => {
		r <- add(r, array_get(self, i));
		if not(eq(i, sub(l, 1))) r <- add(r, ", ")
	});
	r <- add(r, " ]");
	out(r)
};

"########################";
"#         main         #";
"########################";

a: array_new();
out("new:");
array_print(a);

a <- array_push(a, 1);
a <- array_push(a, 4);
a <- array_push(a, 6);
a <- array_push(a, 3);
a <- array_push(a, 2);
out("");
out("pushed:");
array_print(a);

r: array_pop(a);
a <- get(r, "rest");
out("");
out("popped:");
array_print(a);

a <- array_sort(a, (a, b) => { if sup(a, b) 1 else -1 });
out("");
out("sorted:");
array_print(a);