intarray.ml

module Int64Array : sig
  module Array : sig
    type t
    val create_uninitialised : int -> t
    val get : t -> int -> int64
    val set : t -> int -> int64 -> unit
    val unsafe_get : t -> int -> int64
    val unsafe_set : t -> int -> int64 -> unit
  end
end = struct
  module Array = struct
    type t = Bytes.t
    let create_uninitialised sz = Bytes.create (sz * 8)
    external set_raw_64 : Bytes.t -> int -> int64 -> unit = "%caml_bytes_set64"
    external get_raw_64 : Bytes.t -> int -> int64 = "%caml_bytes_get64"
    external unsafe_set_raw_64 : Bytes.t -> int -> int64 -> unit = "%caml_bytes_set64u"
    external unsafe_get_raw_64 : Bytes.t -> int -> int64 = "%caml_bytes_get64u"
    let get arr i = get_raw_64 arr (i * 8)
    let set arr i x = set_raw_64 arr (i * 8) x
    let unsafe_get arr i = unsafe_get_raw_64 arr (i * 8)
    let unsafe_set arr i x = unsafe_set_raw_64 arr (i * 8) x
  end
end

module IntArray : sig
  module Array : sig
    type t
    val create_uninitialised : int -> t
    val get : t -> int -> int
    val set : t -> int -> int -> unit
    val unsafe_get : t -> int -> int
    val unsafe_set : t -> int -> int -> unit
  end
end = struct
  module Array = struct
    type t = Int64Array.Array.t
    let create_uninitialised = Int64Array.Array.create_uninitialised
    let get arr i = Int64.to_int (Int64Array.Array.get arr i)
    let set arr i x = Int64Array.Array.set arr i (Int64.of_int x)
    let unsafe_get arr i = Int64.to_int (Int64Array.Array.unsafe_get arr i)
    let unsafe_set arr i x = Int64Array.Array.unsafe_set arr i (Int64.of_int x)
  end
end


let () =
  let open IntArray in
  let a = Array.create_uninitialised 3 in
  a.(0) <- 42;
  a.(1) <- 100;
  Printf.printf "%d %d %d\n" a.(0) a.(1) a.(2)