blob: bb31fc24c0213c51da9cf48bcf5c2e31bf7bc9f3 (
plain)
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
|
(***********************************************************************)
(* *)
(* OCaml *)
(* *)
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1996 Institut National de Recherche en Informatique et *)
(* en Automatique. All rights reserved. This file is distributed *)
(* under the terms of the Q Public License version 1.0. *)
(* *)
(***********************************************************************)
(* The bank account example, using events and channels *)
open Printf
open Event
type account = int channel * int channel
let account (put_ch, get_ch) =
let rec acc balance =
select [
wrap (send get_ch balance) (fun () -> acc balance);
wrap (receive put_ch) (fun amount ->
if balance + amount < 0 then failwith "negative balance";
acc (balance + amount))
]
in acc 0
let get ((put_ch, get_ch): account) = sync (receive get_ch)
let put ((put_ch, get_ch): account) amount = sync (send put_ch amount)
let _ =
let a : account = (new_channel(), new_channel()) in
ignore (Thread.create account a);
put a 100;
printf "Current balance: %d\n" (get a);
for i = 1 to 99 do put a (-2); put a 1 done;
printf "Final balance: %d\n" (get a)
|
