1Event(3)                         OCaml library                        Event(3)
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NAME

6       Event - First-class synchronous communication.
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Module

9       Module   Event
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Documentation

12       Module Event
13        : sig end
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16       First-class synchronous communication.
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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.
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27       type 'a channel
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30       The type of communication channels carrying values of type 'a .
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34       val new_channel : unit -> 'a channel
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36       Return a new channel.
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39       type +'a event
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42       The type of communication events returning a result of type 'a .
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46       val send : 'a channel -> 'a -> unit event
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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 () .
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54       val receive : 'a channel -> 'a event
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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.
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62       val always : 'a -> 'a event
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65       always v returns an event that is  always  ready  for  synchronization.
66       The result value of this event is v .
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70       val choose : 'a event list -> 'a event
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73       choose  evl returns the event that is the alternative of all the events
74       in the list evl .
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78       val wrap : 'a event -> ('a -> 'b) -> 'b event
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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.
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86       val wrap_abort : 'a event -> (unit -> unit) -> 'a event
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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.
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95       val guard : (unit -> 'a event) -> 'a event
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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.
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104       val sync : 'a event -> 'a
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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.
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113       val select : 'a event list -> 'a
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115       'Synchronize' on an alternative of events.  select evl is shorthand for
116       sync(choose evl) .
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120       val poll : 'a event -> 'a option
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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.
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132OCamldoc                          2020-02-27                          Event(3)