The Coq Proof Assistant

# Library Coq.Strings.ByteVector

Require Import Ascii Basics Bvector String Vector.
Export VectorNotations.
Open Scope program_scope.
Open Scope string_scope.
Definition ByteVector := Vector.t ascii.
Definition ByteNil : ByteVector 0 := Vector.nil ascii.
Definition little_endian_to_string {n : nat} (v : ByteVector n) : string :=
fold_right String v "".
Definition to_string {n : nat} : ByteVector n -> string :=
little_endian_to_string ∘ rev.
Fixpoint little_endian_of_string (s : string) : ByteVector (length s) :=
match s with
| "" => ByteNil
| String b s' => b :: little_endian_of_string s'
end.
Definition of_string (s : string) : ByteVector (length s) :=
rev (little_endian_of_string s).
Fixpoint to_Bvector {n : nat} (v : ByteVector n) : Bvector (n * 8) :=
match v with
| [] => []
| Ascii b0 b1 b2 b3 b4 b5 b6 b7::v' =>
b0::b1::b2::b3::b4::b5::b6::b7::to_Bvector v'
end.
Fixpoint of_Bvector {n : nat} : Bvector (n * 8) -> ByteVector n :=
match n with
| 0 => fun _ => []
| S _ =>
fun v =>
let (b0, v1) := uncons v in
let (b1, v2) := uncons v1 in
let (b2, v3) := uncons v2 in
let (b3, v4) := uncons v3 in
let (b4, v5) := uncons v4 in
let (b5, v6) := uncons v5 in
let (b6, v7) := uncons v6 in
let (b7, v8) := uncons v7 in
Ascii b0 b1 b2 b3 b4 b5 b6 b7::of_Bvector v8
end.