Source file utils.ml

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module Integer : sig
  type t

  val size_in_bytes : t -> int

  val of_bytes : Bytes.t -> t

  val to_bytes : t -> Bytes.t
end = struct
  type t = Bytes.t

  let size_in_bytes x = Bytes.length x

  let of_bytes x = x

  let to_bytes x = x
end

module Stubs = struct
  external create_discriminant : Bytes.t -> int -> int -> Bytes.t -> unit
    = "caml_create_discriminant_stubs"
end

module Utils : sig
  val invalid_group_element : exn

  val unknown_error : exn

  (** [generate_discriminant ?seed size] *)
  val generate_discriminant : ?seed:Bytes.t -> int -> Integer.t
end = struct
  let invalid_group_element =
    Invalid_argument "Invalid input: element not in group"

  let unknown_error = Invalid_argument "Unknown error"

  let generate_discriminant ?(seed = Bytes.empty) size_in_bytes =
    let result = Bytes.create size_in_bytes in
    Stubs.create_discriminant seed (Bytes.length seed) size_in_bytes result ;
    Integer.of_bytes result
end

include Utils