module Pure :
  sig
    type t = V of int | A of t * t | L of t | B
    val print : ?l:string list -> t -> string
    val lift : int -> t -> t
    val unwind : ?tbl:('a list * t * 'a list as 'a, t) Hashtbl.t -> 'a -> t
    val mwhd : (('a * t * ('b list as 'c) as 'b) list as 'a) * t * 'c -> t
  end

module Scott :
  sig
    val mk_n : int -> Pure.t
    val dummy : Pure.t
    val mk_match : Pure.t -> (int * Pure.t) list -> Pure.t
  end