Instance bool_Serializer : Serializer bool.

(* this needs to go here because we need the bool_Serializer instance *)
Lemma fold_append_unwrap :
forall {S A : Type}
(f : byte -> S -> fold_state S A) (s : S)
(b : byte) (tail : IOStreamWriter.t) (bin : list byte),
ByteListReader.unwrap (ByteListReader.fold f s)
(IOStreamWriter.unwrap (IOStreamWriter.append
(fun _ => (serialize b))
(fun _ => tail)) ++ bin) =
match f b s with
| Done a => Some(a, IOStreamWriter.unwrap tail ++ bin)
| More s => ByteListReader.unwrap (ByteListReader.fold f s)
(IOStreamWriter.unwrap tail ++ bin)
| Error => None
end.