proposition: Lemma update_app_left {X} (x : X) l1 l2 i : i < length l1 -> update i (l1 ++ l2) x = update i l1 x ++ l2.
proof: Proof. induction l1 in i |- *; cbn. - lia. - intros Hi. destruct i; cbn. + reflexivity. + rewrite IHl1. 1: reflexivity. lia. Qed.
imports: Undecidability.MinskyMachines(MM_computable MM_sss mm_utils) Undecidability.StackMachines(BSM_computable) Undecidability.Shared.Libs.DLW(vec pos sss subcode) Lia Vector Nat Arith List Undecidability.MinskyMachines.MM(mm_defs mm_utils mm_comp_strong)