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(* 02110-1301 USA                                                     *)
Section my_MapFold.
Variable M : Set.
Variable neutral : M.
Variable op : M -> M -> M.
Variable R : relation M.
Definition F (A : Set) (f : ad -> A -> M) (r : ad * A)
(m : M) := let (a, y) := r in op (f a y) m.
Hypothesis eq_R : equiv _ R.
Hypothesis op_assoc : forall a b c : M, R (op (op a b) c) (op a (op b c)).
Hypothesis op_neutral_left : forall a : M, R (op neutral a) a.
Hypothesis op_neutral_right : forall a : M, R (op a neutral) a.
Hypothesis
op_eq : forall a b a1 b1 : M, R a a1 -> R b b1 -> R (op a b) (op a1 b1).

Lemma op_eq_2 : forall a b b1 : M, R b b1 -> R (op a b) (op a b1).