proposition: Lemma nth_error_nth {A} (ls : list A) (n : nat) (y : A) : nth n ls y = match nth_error ls n with | Some x => x | None => y end.
proof: Proof. revert n; induction ls; intros [|n]; simpl in *; intros; try discriminate; unfold value in *; eauto. Qed.
imports: Fiat.Common.Coq__8_4__8_5__Compat Coq.ZArith.ZArith Coq.Lists.List Coq.Lists.SetoidList Coq.Bool.Bool Fiat.Common Fiat.Common.List.Operations Fiat.Common.Equality Fiat.Common.List.FlattenList Fiat.Common.LogicFacts