1Event(3)                         OCaml library                        Event(3)
2
3
4

NAME

6       Event - First-class synchronous communication.
7

Module

9       Module   Event
10

Documentation

12       Module Event
13        : sig end
14
15
16       First-class synchronous communication.
17
18       This  module  implements  synchronous  inter-thread communications over
19       channels. As in John Reppy's Concurrent ML  system,  the  communication
20       events  are first-class values: they can be built and combined indepen‐
21       dently before being offered for communication.
22
23
24
25
26
27       type 'a channel
28
29
30       The type of communication channels carrying values of type 'a .
31
32
33
34       val new_channel : unit -> 'a channel
35
36       Return a new channel.
37
38
39       type +'a event
40
41
42       The type of communication events returning a result of type 'a .
43
44
45
46       val send : 'a channel -> 'a -> unit event
47
48
49       send ch v returns the event consisting in sending the value v over  the
50       channel ch . The result value of this event is () .
51
52
53
54       val receive : 'a channel -> 'a event
55
56
57       receive  ch  returns the event consisting in receiving a value from the
58       channel ch . The result value of this event is the value received.
59
60
61
62       val always : 'a -> 'a event
63
64
65       always v returns an event that is  always  ready  for  synchronization.
66       The result value of this event is v .
67
68
69
70       val choose : 'a event list -> 'a event
71
72
73       choose  evl returns the event that is the alternative of all the events
74       in the list evl .
75
76
77
78       val wrap : 'a event -> ('a -> 'b) -> 'b event
79
80
81       wrap ev fn returns the event that performs the same  communications  as
82       ev , then applies the post-processing function fn on the return value.
83
84
85
86       val wrap_abort : 'a event -> (unit -> unit) -> 'a event
87
88
89       wrap_abort  ev  fn  returns the event that performs the same communica‐
90       tions as ev , but if it is not selected the function fn is called after
91       the synchronization.
92
93
94
95       val guard : (unit -> 'a event) -> 'a event
96
97
98       guard  fn  returns the event that, when synchronized, computes fn() and
99       behaves as the resulting event.  This  enables  computing  events  with
100       side-effects at the time of the synchronization operation.
101
102
103
104       val sync : 'a event -> 'a
105
106       'Synchronize'  on  an  event: offer all the communication possibilities
107       specified in the event to the outside world, and block until one of the
108       communications  succeed.  The  result  value  of  that communication is
109       returned.
110
111
112
113       val select : 'a event list -> 'a
114
115       'Synchronize' on an alternative of events.  select evl is shorthand for
116       sync(choose evl) .
117
118
119
120       val poll : 'a event -> 'a option
121
122       Non-blocking version of Event.sync : offer all the communication possi‐
123       bilities specified in the event to the outside world, and  if  one  can
124       take  place  immediately,  perform  it and return Some r where r is the
125       result value of that communication.   Otherwise,  return  None  without
126       blocking.
127
128
129
130
131
132OCamldoc                          2019-07-30                          Event(3)
Impressum