# Filter: sort with a given `comparator`.
	# Important: require O(n) memory.
	#
	#     assert ["a", "c", "b"].iterator.sort_with(alpha_comparator).to_a  == ["a", "b", "c"]
	fun sort_with(comparator: Comparator): Iterator[E]
	do
		var a = self.to_a
		comparator.sort(a)
		return a.iterator
	end