This module controls the ``main-loop'' of Lwt.
val run : 'a Lwt.t -> 'a
run p calls the Lwt scheduler repeatedly until
p resolves, and returns the value of
p if it is fulfilled. If
p is rejected with an exception, that exception is raised.
Every native or bytecode program that uses Lwt should always use this function for evaluating a promise at the top level (such as its main function or main loop), otherwise promises that depend on I/O operations will not be resolved.
let main () = Lwt_io.write_line Lwt_io.stdout "hello world" let () = Lwt_main.run @@ main ()
Lwt_main.run is not available, but neither it's necessary since the JS environment automatically takes care of the I/O considerations.
Note that you should avoid using
run inside threads
- The calling threads will not resume before
- Successive invocations of
runare serialized: an invocation of
runwill not terminate before all subsequent invocations are terminated.
Note also that it is not safe to call
run in a function registered with
Pervasives.at_exit, use the
at_exit function of this module instead.
val yield : unit -> unit Lwt.t
yield () is a threads which suspends itself and then resumes as soon as possible and terminates.
val enter_iter_hooks : ( unit -> unit ) Lwt_sequence.t
Functions that are called before the main iteration.
val leave_iter_hooks : ( unit -> unit ) Lwt_sequence.t
Functions that are called after the main iteration.
Sets of functions executed just before the program exit.
- each hook is called exactly one time
- exceptions raised by hooks are ignored
val at_exit : ( unit -> unit Lwt.t ) -> unit
at_exit hook adds hook at the left of