proposition: Lemma firstn_skipn_self'' {A} : forall (n m o : nat) (l : list A), length l = n + m + o -> decides true ((firstn n l ++ firstn m (skipn n l) ++ firstn o (skipn (n + m) l))%list = l).
proof: Proof. intros; eapply firstn_skipn_self'. omega. 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