bitset.ml
(*****************************************************************************)
(* *)
(* Open Source License *)
(* Copyright (c) 2022 Nomadic Labs <contact@nomadic-labs.com> *)
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(*****************************************************************************)
type t = Z.t
type error += Invalid_position of int
let encoding = Data_encoding.z
let empty = Z.zero
let mem field pos =
error_when Compare.Int.(pos < 0) (Invalid_position pos) >>? fun () ->
ok @@ Z.testbit field pos
let add field pos =
error_when Compare.Int.(pos < 0) (Invalid_position pos) >>? fun () ->
ok @@ Z.logor field Z.(shift_left one pos)
let from_list positions = List.fold_left_e add empty positions
let fill ~length =
error_when Compare.Int.(length < 0) (Invalid_position length) >>? fun () ->
ok Z.(pred (shift_left one length))
let inter = Z.logand
let diff b1 b2 = Z.logand b1 (Z.lognot b2)
let () =
let open Data_encoding in
register_error_kind
`Permanent
~id:"bitfield_invalid_position"
~title:"Invalid bitfield’s position"
~description:"Bitfields does not accept negative positions"
(obj1 (req "position" int31))
(function Invalid_position i -> Some i | _ -> None)
(fun i -> Invalid_position i)
let occupied_size_in_bits = Z.numbits
module Internal_for_tests = struct
let to_z z = z
end