Remove problem related to the PR#2920 in OCaml BTS

types/types.ml

@@ -130,7 +130,6 @@ end
 
 type pair_kind = [ `Normal | `XML ]
 
-
 module rec Descr : 
 sig
   type s = {
@@ -144,7 +143,6 @@ sig
     abstract: Abstract.t;
     absent: bool
   }
-
   include Custom.T with type t = s
   val empty: t
 end =
@@ -258,25 +256,13 @@ struct
   let mk id d = { id = id; cu = Compunit.current (); descr = d }
 end
 
-(* See PR#2920 in OCaml BTS *)
-and NodeT : Custom.T with type t = Node.t =
-struct
-  type t = Node.t
-  let dump x = Node.dump x
-  let check x = Node.check x
-  let equal x = Node.equal x
-  let hash x = Node.hash x
-  let compare x = Node.compare x
-end
-
-
 (* It is also possible to use Boolean instead of Bool here;
    need to analyze when each one is more efficient *)
 and BoolPair : Bool.S with type elem = Node.t * Node.t = 
-(*Bool.Simplify*)(Bool.Make)(Custom.Pair(NodeT)(NodeT))
+(*Bool.Simplify*)(Bool.Make)(Custom.Pair(Node)(Node))
 
 and BoolRec : Bool.S with type elem = bool * Node.t label_map =
-(*Bool.Simplify*)(Bool.Make)(Custom.Pair(Custom.Bool)(LabelSet.MakeMap(NodeT)))
+(*Bool.Simplify*)(Bool.Make)(Custom.Pair(Custom.Bool)(LabelSet.MakeMap(Node)))
 
 module DescrHash = Hashtbl.Make(Descr)
 module DescrMap = Map.Make(Descr)