onEvent' (Elem el) et hnd =
  do cb <- asyncCallback1 hnd
     js_addEventListener el e cb
  where
    e = pack (eventName et)
onEvent' (Elem el) et hnd =
  do cb <- asyncCallback1 hnd
     js_addEventListener el e cb
  where
    e = pack (eventName et)
onEvent' (Elem el) et hnd =
  do cb <- asyncCallback1 hnd
     js_addEventListener el e cb
  where
    e = pack (eventName et)