fact: Fixpoint fold {A: Type} (f: key -> elt -> A -> A) (t: tree) (base: A) : A := match t with | Leaf => base | Node _ l x e r => fold f r (f x e (fold f l base)) end.
imports: Coq(Bool Arith BinInt FunInd) Coq(Orders OrdersFacts OrdersLists) MMaps(Comparisons Interface OrdList)