(** Types *)

type t

type kind =
  | Three  of  Powers.t
  | Four   of (int * int * int * int)
  | Six    of (Powers.t * Powers.t)
  | Nine   of (Powers.t * Powers.t * Powers.t)
  | Twelve of (Powers.t * Powers.t * Powers.t * Powers.t)


(** Conversions *)

val of_powers_three  : Powers.t -> t
(** Create from a ~Powers.t~ *)

val of_powers_six    : Powers.t -> Powers.t -> t
(** Create from two ~Powers.t~ *)

val of_powers_nine   : Powers.t -> Powers.t -> Powers.t -> t
(** Create from three ~Powers.t~ *)

val of_powers_twelve : Powers.t -> Powers.t -> Powers.t -> Powers.t -> t
(** Create from four ~Powers.t~ *)

val of_powers        : kind -> t
(** Create using the ~kind~ type *)

val of_int_array     : int array -> t
(** Convert from an ~int~ array *)

val of_int_four      : int -> int -> int -> int -> t
(** Create from four ~ints~ *)

val to_int_array     : t -> int array
(** Convert to an ~int~ array *)

val to_powers        : t -> kind
(** Convert to an ~Powers.t~ array *)

val to_string        : t -> string
(** Pretty printing *)


(** Functions for hash tables *)

val hash    : t -> int
(** Associates a nonnegative integer to any Zkey *)

val equal   : t -> t -> bool
(** The equal function. True if two Zkeys are equal *)

val compare : t -> t -> int
(** Comparison function, used for sorting *)


(** Printers *)

val pp : Format.formatter -> t -> unit