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|
type t =
{ len : int
; bits : Bytes.t
}
let byte s i = Char.code (Bytes.unsafe_get s i)
let set_byte s i x = Bytes.unsafe_set s i (Char.chr x)
let length t = t.len
let unsafe_set v n b =
let i = n lsr 3 in
let c = byte v.bits i in
let mask = 1 lsl (n land 7) in
set_byte v.bits i (if b then c lor mask else c land lnot mask)
;;
let set v n b =
if n < 0 || n >= v.len then invalid_arg "Bit_vector.set";
unsafe_set v n b
;;
let unsafe_get v n =
let i = n lsr 3 in
byte v.bits i land (1 lsl (n land 7)) > 0
;;
let get v n =
if n < 0 || n >= v.len then invalid_arg "Bit_vector.get";
unsafe_get v n
;;
let reset_zero t = Bytes.fill t.bits 0 (Bytes.length t.bits) '\000'
let create_zero len =
let bits =
let r = len land 7 in
let q = len lsr 3 in
let len = if r = 0 then q else q + 1 in
Bytes.make len '\000'
in
{ len; bits }
;;
let pp fmt { len; bits } =
let len fmt () = Fmt.sexp fmt "len" Fmt.int len in
let bits fmt () = Fmt.sexp fmt "bits" Fmt.bytes bits in
Format.fprintf fmt "%a@.%a@." len () bits ()
;;
|
