Definition cardinal_e_2 ee :=
   (cardinal_e (fst ee) + cardinal_e (snd ee))%nat.Program Fixpoint compare_aux (ee:Raw.enumeration D.t * Raw.enumeration D.t)
   { measure (cardinal_e_2 ee) } : comparison :=
  match ee with
  | (Raw.End _, Raw.End _) => Eq
  | (Raw.End _, Raw.More _ _ _ _) => Lt
  | (Raw.More _ _ _ _, Raw.End _) => Gt
  | (Raw.More x1 d1 r1 e1, Raw.More x2 d2 r2 e2) =>
      match X.compare x1 x2 with
      | EQ _ => match D.compare d1 d2 with
                | EQ _ => compare_aux (Raw.cons r1 e1, Raw.cons r2 e2)
                | LT _ => Lt
                | GT _ => Gt
                end
      | LT _ => Lt
      | GT _ => Gt
      end
  end.Definition Cmp c :=
   match c with
    | Eq => LO.eq_list
    | Lt => LO.lt_list
    | Gt => (fun l1 l2 => LO.lt_list l2 l1)
   end.

Lemma cons_Cmp : forall c x1 x2 d1 d2 l1 l2, X.eq x1 x2 -> D.eq d1 d2 -> Cmp c l1 l2 -> Cmp c ((x1,d1)::l1) ((x2,d2)::l2).