class ['a] delay_engine : float -> (unit -> 'a #engine) -> Unixqueue.event_system -> ['a] engine
['a]
float -> (unit -> 'a #engine) -> Unixqueue.event_system ->
engine
let de = delay_engine d f esys: The engine e = f() is created after d seconds, and the result of e becomes the result of de.
let de = delay_engine d f esys
e = f()
d
e
de
