proposition: Lemma decides_firstn_self {A} : forall (l1 : list A), decides true (firstn (length l1) l1 = l1).
proof: Proof. intros; apply firstn_self. Qed.
imports: Fiat.Common.Coq__8_4__8_5__Compat Coq.Bool.Bool Coq.ZArith.ZArith Coq.Lists.List Fiat.Common.DecideableEnsembles Fiat.Common.EnumType Fiat.Common.BoundedLookup Fiat.Common Fiat.Common.ilist Fiat.Common.Tactics.CacheStringConstant Fiat.Common.IterateBoundedIndex Fiat.Computation Bedrock.Word