proposition: Lemma override_new_val: forall (V: Type) m k (v: V), (override m k v) k = v.
proof: Proof. intros. unfold override. rewrite eq_nat_dec_eq. reflexivity. Qed.
imports: Coq(FunctionalExtensionality Arith Lia) Coq(Arith.Peano_dec Arith.Compare_dec) Coq(Relations.Relation_Operators) Coq(List) Chapar(Predefs)