fact: Fixpoint Vector_nth_opt {A : Type} {n : nat} (v : Vector.t A n) (m : nat) : option A := match m, v with | 0, Vector.cons a _ _ => Some a | S m', Vector.cons _ _ v' => Vector_nth_opt v' m' | _, _ => None end.
imports: Fiat.Common.Coq__8_4__8_5__Compat Bedrock.Word Coq.ZArith.ZArith Coq.NArith.NArith Coq.Arith.Arith Coq.Numbers.Natural.Peano.NPeano Coq.Logic.Eqdep_dec Fiat.Narcissus.Common.Specs Fiat.Narcissus.BinLib.Core Fiat.Narcissus.BinLib.AlignedByteString