The documentation for the execute function in Reactive.Banana.Frameworks states that "there is no guarantee about the order in which actions are performed."
I am not sure which order is implied here. Since the event only fires immediately after one action, there is not much guarantee here, therefore the most likely scenario that I can imagine is this:
a :: MomentIO (Event t) a = ... b :: MomentIO (Event t) b = ... makeEvent :: MomentIO (Event (MomentIO (Event t)) makeEvent = fromAddHandler $ ... -- Some AddHandler that first fires a -- and later fires b network :: MomentIO () network = do ... newEvents <- makeEvent ts <- execute newEvents >>= switchE ...
The non-guarantee that I can imagine is that the execution order of a and b switched, so b is executed first. If we assume that a and b change the behavior of a widget (using liftIO ), and then register the corresponding event handler (unregisters the previously registered one), switching the execution order of a and b will be fatal, since it will leave the widget in a state when it does not start the handlers that it should run. Since I don't see which use cases for execute are still useful if my script is correct, I believe the documentation actually means something else.
Can anyone clarify what the documentation is trying to say here?
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