EnumValueMap allows mapping of enum value keys to arbitrary values.
Keys are compared by value and recursively over their parameters. If any
parameter is not an enum value, Reflect.compare is used to compare them.
Removes all keys from this BalancedTree.
Tells if key is bound to a value.
This method returns true even if key is bound to null.
If key is null, the result is unspecified.
Returns the value key is bound to.
If key is not bound to any value, null is returned.
Iterates over the bound values of this BalancedTree.
This operation is performed in-order.
Iterates over the keys of this BalancedTree.
Removes the current binding of key.
If key has no binding, this BalancedTree is unchanged and false is
Otherwise the binding of key is removed and true is returned.
Binds key to value.
If key is already bound to a value, that binding disappears.