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(* Open Source License                                                       *)
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(* Copyright (c) 2022 Trili Tech, <contact@trili.tech>                       *)
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(** Values are versioned so that they can be modified in future iterations
    of the protocol.

    The [versioned_encoding] corresponds to the one defined by the protocol.
*)

module type S = sig
  (** The type of values that is currently used. *)
  type t

  (** The type of {e versioned} values, including the one that is currently used
      and the previous ones. *)
  type versioned

  (** Encoding for versioned values, corresponds to the one defined by the
      protocol. *)
  val versioned_encoding : versioned Data_encoding.t

  (** Conversion to the currently used representation. In practice this function
      must provide ways to translate values of older versions to the latest
      one. *)
  val of_versioned : versioned -> t

  (** Wrapping a current value as a versioned one. *)
  val to_versioned : t -> versioned
end