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
82
83
84
85
86
|
(* Basic counting module.
Copyright (C) 2006 Merjis Ltd.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*)
type 'a t = ('a, int ref) Hashtbl.t
let create () =
Hashtbl.create 13
let get_ref counter thing =
try
Hashtbl.find counter thing
with
Not_found ->
let r = ref 0 in
Hashtbl.add counter thing r;
r
let incr counter thing =
let r = get_ref counter thing in
incr r
let decr counter thing =
let r = get_ref counter thing in
decr r
let add counter thing n =
let r = get_ref counter thing in
r := !r + n
let sub counter thing n =
let r = get_ref counter thing in
r := !r - n
let set counter thing n =
let r = get_ref counter thing in
r := n
(* Don't use get_ref, to avoid unnecessarily creating 'ref 0's. *)
let get counter thing =
try
!(Hashtbl.find counter thing)
with
Not_found -> 0
(* This is a common pair of operations, worth optimising. *)
let incr_get counter thing =
let r = get_ref counter thing in
Pervasives.incr r;
!r
let zero = Hashtbl.remove
let read counter =
let counts =
Hashtbl.fold (
fun thing r xs ->
let r = !r in
if r <> 0 then (r, thing) :: xs
else xs
) counter [] in
List.sort (fun (a, _) (b, _) -> compare (b : int) (a : int)) counts
let length = Hashtbl.length
let total counter =
let total = ref 0 in
Hashtbl.iter (fun _ r -> total := !total + !r) counter;
!total
let clear = Hashtbl.clear
|
