module type EqSig =
sig
  type t;;
  val equal : t -> t -> bool
end;;

module EqInt : EqSig with type t = int =
struct
  type t = int;;
  let equal = (=);;
end;;

module BigFunctor(E : EqSig) =
struct
  let eqall x y z = E.equal x y && E.equal y z;;
  let alldiff x y z = not (E.equal x y) &&
                      not (E.equal x z) &&
                      not (E.equal y z);;
end;;

module FactoredFunctorPart1(E : EqSig) =
struct
  module E = E
  let eqall x y z = E.equal x y && E.equal y z;;
end;;

module FactoredFunctorPart2(E : EqSig) =
struct
  module E = E
  let alldiff x y z = not (E.equal x y) &&
                      not (E.equal x z) &&
                      not (E.equal y z);;
end;;

module FactoredFunctor(E : EqSig) =
struct
  module FactoredPart1 = FactoredFunctorPart1(E);;
  include (FactoredPart1 : module type of FactoredPart1 with module E := E);;
  module FactoredPart2 = FactoredFunctorPart2(E);;
  include (FactoredPart2 : module type of FactoredPart2 with module E := E);;
end;;