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(** Functions for sampling (pk,pkh,sk) triplets.

    This module provides an implementation for finite pools of random
    (pk,pkh,sk) triplets. The pools grows to the target [size] as the user
    samples from it. When the target size is reached, sampling is performed
    in a round-robin fashion.
 *)

module type Param_S = sig
  (** Maximal size of the key pool. *)
  val size : int

  (** Algorithm to use for triplet generation. *)
  val algo : [`Algo of Signature.algo | `Default]
end

module type Finite_key_pool_S = sig
  (** Sample a public key from the pool. *)
  val pk : Signature.public_key Base_samplers.sampler

  (** Sample a public key hash from the pool. *)
  val pkh : Signature.public_key_hash Base_samplers.sampler

  (** Sample a secret key from the pool. *)
  val sk : Signature.secret_key Base_samplers.sampler

  (** Sample a (pkh, pk, sk) triplet from the pool. *)
  val all :
    (Signature.public_key_hash * Signature.public_key * Signature.secret_key)
    Base_samplers.sampler
end

(** Create a finite key pool. *)
module Make_finite_key_pool (Arg : Param_S) : Finite_key_pool_S