reflex-test.hs

bar :: (TriggerEvent t m, PerformEvent t m) => Int -> m ()
bar x = do
  (event, triggerEvent) <- newTriggerEvent
  performEvent_ $
    event `ffor` \x -> do
      -- ....
      pure ()

foo :: (TriggerEvent t m, PerformEvent t m, TriggerEvent t0 (Performable m), PerformEvent t0 (Performable m)) => m ()
foo = do
  (event, triggerEvent) <- newTriggerEvent
  performEvent_ $
    event `ffor` \x -> do
      -- subscription to `bar` begins dynamically based on the value of `x`
      bar x
      pure ()