private class BinTreeMapIterator[K: Comparable, E]
	super MapIterator[K, E]

	var tree: BinTreeMap[K, E]
	var current: nullable BinTreeNode[K, E] = null

	init do current = tree.first_node

	redef fun is_ok do return not current == null
	redef fun next do current = current.next
	redef fun item do return current.value
	redef fun key do do return current.key
end