- val iter : (Tree.t -> unit) -> t -> unit
- val fold : (Tree.t -> 'a -> 'a) -> t -> 'a -> 'a
- val map : (Tree.t -> Tree.t) -> t -> t
+ val iter : (elt -> unit) -> t -> unit
+ val fold : (elt -> 'a -> 'a) -> t -> 'a -> 'a
+ val map : (elt -> elt) -> t -> t