proposition: Lemma Eqdom_equal (m m' : t elt) : Eqdom m m' <-> equal (fun _ _ => true) m m' = true.
proof: Proof. rewrite equal_spec. unfold Equivb, Cmp, Equiv. firstorder. Qed.
imports: Coq(Bool Equalities Orders OrdersFacts OrdersLists) Coq(Morphisms Permutation SetoidPermutation) MMaps(Utils Comparisons Interface)