map

class Map < BinaryTree

A Map is a cross between an array and a hash. It does not have O(1) element access like a hash, but its elements are ordered. This Map is a BinaryTree, but an ideal Map would probably be an RB Tree.

TODO: Perhaps it would be nice to be able to customize what kind of implementation we get when we ask for a map? Perhaps Map should just be a constructor for other classes?

Requires