INCLUDE "utils.ml"

include Hlist_sig

module type HConsBuilder =
  functor (H : Common_sig.HashedType) -> Hcons.S with type data = H.t

module Builder (HCB : HConsBuilder) (H : Hcons.Abstract) :
  S with type elt = H.t =
struct
  type elt = H.t

  module rec Node : Hcons.S with type data = Data.t = HCB(Data)
                            and Data : Common_sig.HashedType with type t = (elt, Node.t) node =
  struct
    type t = (elt, Node.t) node
    let equal x y =
      match x,y with
      | Nil, Nil -> true
      | Cons(e1, l1), Cons(e2, l2) -> e1 == e2 && l1 == l2
      | _ -> false

    let hash = function
    | Nil -> 0
    | Cons(e, l) -> HASHINT3 (PRIME1, Uid.to_int (H.uid e), Uid.to_int (Node.uid l))
  end

  include Node

  let nil = make Nil

  let rec sorted_cons e l =
    match l.Node.node with
      |	Nil -> Node.make (Cons(e, l))
      | Cons (x, ll) ->
	  if H.uid e < H.uid x
	  then Node.make (Cons(e, l))
	  else Node.make (Cons(x, sorted_cons e ll))

  let cons e l =
    Node.make(Cons(e, l))

  let cons ?(sorted=true) e l =
    if sorted then sorted_cons e l else cons e l

  let hd = function { Node.node = Cons(e, _); _ } -> e | _ -> failwith "hd"
  let tl = function { Node.node = Cons(_, l); _ } -> l | _ -> failwith "tl"

  let fold f l acc =
    let rec loop acc l = match l.Node.node with
      | Nil -> acc
      | Cons (a, aa) -> loop (f a acc) aa
    in
      loop acc l

  let map f l  =
    let rec loop l = match l.Node.node with
      | Nil -> nil
      | Cons(a, aa) -> cons (f a) (loop aa)
    in
      loop l

  let iter f l =
    let rec loop l = match l.Node.node with
      | Nil -> ()
      | Cons(a,aa) ->  (f a);(loop aa)
    in
      loop l

  let rev l = fold cons l nil
  let rev_map f l = fold (fun x acc -> cons (f x) acc) l nil
  let length l = fold (fun _ c -> c+1) l 0
  let rec mem e l =
    match l.Node.node with
      | Nil -> false
      | Cons (x, ll) -> x == e || mem e ll

end

module Make = Builder(Hcons.Make)
module Weak = Builder(Hcons.Weak)