proposition: Lemma add_o m x y e : find y (add x e m) = if K.eq_dec x y then Some e else find y m.
proof: Proof. destruct (K.eq_dec x y); auto with map. Qed.
imports: Coq(Bool Equalities Orders OrdersFacts OrdersLists) Coq(Morphisms Permutation SetoidPermutation) MMaps(Utils Comparisons Interface)