module Event:sig..end
First-class synchronous communication.
This module implements synchronous inter-thread communications over channels. As in John Reppy's Concurrent ML system, the communication events are first-class values: they can be built and combined independently before being offered for communication.
type 'a channel
The type of communication channels carrying values of type 'a.
val new_channel : unit -> 'a channelReturn a new channel.
type +'a event
The type of communication events returning a result of type 'a.
val send : 'a channel -> 'a -> unit eventsend ch v returns the event consisting in sending the value v
over the channel ch. The result value of this event is ().
val receive : 'a channel -> 'a eventreceive ch returns the event consisting in receiving a value
from the channel ch. The result value of this event is the
value received.
val always : 'a -> 'a eventalways v returns an event that is always ready for
synchronization. The result value of this event is v.
val choose : 'a event list -> 'a eventchoose evl returns the event that is the alternative of
all the events in the list evl.
val wrap : 'a event -> ('a -> 'b) -> 'b eventwrap ev fn returns the event that performs the same communications
as ev, then applies the post-processing function fn
on the return value.
val wrap_abort : 'a event -> (unit -> unit) -> 'a eventwrap_abort ev fn returns the event that performs
the same communications as ev, but if it is not selected
the function fn is called after the synchronization.
val guard : (unit -> 'a event) -> 'a eventguard fn returns the event that, when synchronized, computes
fn() and behaves as the resulting event. This allows to
compute events with side-effects at the time of the synchronization
operation.
val sync : 'a event -> 'a'Synchronize' on an event: offer all the communication possibilities specified in the event to the outside world, and block until one of the communications succeed. The result value of that communication is returned.
val select : 'a event list -> 'a'Synchronize' on an alternative of events.
select evl is shorthand for sync(choose evl).
val poll : 'a event -> 'a optionNon-blocking version of Event.sync: offer all the communication
possibilities specified in the event to the outside world,
and if one can take place immediately, perform it and return
Some r where r is the result value of that communication.
Otherwise, return None without blocking.