forked from MLstate/opalang
-
Notifications
You must be signed in to change notification settings - Fork 0
/
weakHashtbl.ml
81 lines (62 loc) · 1.9 KB
/
weakHashtbl.ml
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
(*
Copyright © 2011 MLstate
This file is part of OPA.
OPA is free software: you can redistribute it and/or modify it under the
terms of the GNU Affero General Public License, version 3, as published by
the Free Software Foundation.
OPA is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for
more details.
You should have received a copy of the GNU Affero General Public License
along with OPA. If not, see <http://www.gnu.org/licenses/>.
*)
(* http://remi.vanicat.free.fr/ocaml/hweak/ *)
(* Perhaps we can replace this module by (modified?) above hweak
implementation... ? *)
module type WeakedType = sig
type t
val compare : t -> t -> int
val hash : t -> int
end
module Make (HK : Hashtbl.HashedType)(HD : WeakedType) = struct
module WS = Weak.Make
(struct
include HD
let equal a b = HD.compare a b = 0
end)
module HT = Hashtbl.Make(HK)
type key = HK.t
module S = Set.Make(HD)
type t = {
htbl : HD.t HT.t;
wset : WS.t;
mutable strong : S.t;
}
let create i = {
htbl = HT.create i;
wset = WS.create i;
strong = S.empty;
}
let remove t k =
try
let v = HT.find t.htbl k in
WS.remove t.wset v;
HT.remove t.htbl k;
t.strong <- S.remove v t.strong
with Not_found -> ()
let add t k v =
let vcopy = Obj.obj (Obj.dup (Obj.repr v)) in
HT.add t.htbl k vcopy;
WS.add t.wset v;
Gc.finalise (fun _ -> HT.remove t.htbl (k:HK.t)) v
let mem t k = (HT.mem t.htbl k)
let find t k = WS.find t.wset (HT.find t.htbl k)
let strong t k v =
if not (mem t k) then add t k v;
t.strong <- S.add v t.strong
let relax t k =
t.strong <- S.remove (find t k) t.strong
let size t =
HT.length t.htbl
end