Hex (hex.Hex)

module Digit : sig ... end

val hex_char_of_int_exn : int -> char

module Sequence_be : sig ... end

val decode : 
  ?reverse:bool ->
  ?pos:int ->
  init:( int -> f:( int -> Core_kernel.Char.t ) -> 'a ) ->
  string ->
  'b

val encode : ?reverse:bool -> string -> string

module Safe : sig ... end