Step 4

let { worker_poll_thunk = THUNK(poll_1 monadIO) } in then_1 monadIO worker_poll_thunk $0

$0

BLACKHOLE

main

BLACKHOLE

monadIO

CON(Monad returnIO thenIO)

poll

FUN(monad ->
       let {
          ret_thunk = THUNK(return_1 monad unit);
          poll_poll_thunk = THUNK(poll_1 monad)
       } in then_1 monad ret_thunk poll_poll_thunk)

realWorld

CON(RealWorld)

return

FUN(monad ->
       case monad of {
          Monad return then -> return
       })

returnIO

FUN(x s -> (# s, x #))

then

FUN(monad ->
       case monad of {
          Monad return then -> then
       })

thenIO

FUN(m k s ->
       case m_? s of {
          (# new_s, result #) -> k_? new_s
       })

unit

CON(Unit)