ArrayLists used to store an allocator at init time and then use it for appends and whatnot afterwards. It was decided that this hid allocations and wasn't appropriate for the standard library.
It is of course trivial to define your own arraylist type that wraps an allocator on initialisation if you so wish.
It is of course trivial to define your own arraylist type that wraps an allocator on initialisation if you so wish.