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(** Type for a module representing the ℤ/nℤ ring*)
module type ZN = sig

  type t
  include S.B58_DATA with type t := t
  include S.ENCODER with type t := t

  val zero : t
  val one  : t
  val n : Z.t
  val (+)       : t -> t -> t
  val ( * )     : t -> t -> t
  val (-)       : t -> t -> t
  val (=)    : t -> t -> bool

  (** Converts an integer to a ring element *)
  val of_int    : int -> t

  (** Converts a Zarith integer to a ring element *)
  val of_Z      : Z.t -> t

  (** Provides an integer representation between 0 and n-1 of an element *)
  val to_Z      : t -> Z.t

  (** Converts a string of bytes to an integer modulo n, requires the string of
      byte to represent an integer between 0 and n-1 and checks the length of
      the string for sanity*)
  val of_bits_exn   : String.t -> t

  (** Converts a ring element to a byte representation *)
  val to_bits : t -> String.t

  (** Modular exponentiation *)
  val pow       : t -> Z.t -> t

  (** Returns the inverse of a in ℤ/nℤ, maybe *)
  val inv       : t -> t option

end


(** Type of a module wrapping an integer. *)
module type INT = sig
  val n : Z.t
end

(** Functor to build the ℤ/nℤ ring given n*)
module MakeZn : functor (N : INT) (B : sig val b58_prefix : string end) -> ZN