type writer
type reader

val writer_create : unit -> writer
val write_bit : writer -> bool -> unit
val write_bits : writer -> Z.t -> int -> unit
val writer_to_bytes : writer -> bytes
val writer_pos : writer -> int

val reader_create : bytes -> reader
val read_bit : reader -> bool
val read_bits : reader -> int -> Z.t
val reader_pos : reader -> int
val count_zero_bits_until_one : reader -> int