fact: Fixpoint xmapi (m : t A) (i : key) : t B := match m with | Leaf => Leaf | Node l o r => Node (xmapi l (i~0)) (f (rev i) o) (xmapi r (i~1)) end.
imports: Coq(Bool PeanoNat BinPos Orders OrdersEx OrdersLists) MMaps(Utils Comparisons Interface)