ocaml/test/Moretest/recmod/17ok.ml

43 lines
965 B
OCaml

(* A synthetic example of bootstrapped data structure
(suggested by J-C Filliatre) *)
module type ORD = sig
type t
val compare : t -> t -> int
end
module type SET = sig
type elt
type t
val iter : (elt -> unit) -> t -> unit
end
type 'a tree = E | N of 'a tree * 'a * 'a tree
module Bootstrap2
(MakeDiet : functor (X: ORD) -> SET with type t = X.t tree and type elt = X.t)
: SET with type elt = int =
struct
type elt = int
module rec Elt : sig
type t = I of int * int | D of int * Diet.t * int
val compare : t -> t -> int
val iter : (int -> unit) -> t -> unit
end =
struct
type t = I of int * int | D of int * Diet.t * int
let compare x1 x2 = 0
let rec iter f = function
| I (l, r) -> for i = l to r do f i done
| D (_, d, _) -> Diet.iter (iter f) d
end
and Diet : SET with type t = Elt.t tree and type elt = Elt.t = MakeDiet(Elt)
type t = Diet.t
let iter f = Diet.iter (Elt.iter f)
end