LaunchMissiles.hs

{-# LANGUAGE Safe #-}
{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE DuplicateRecordFields #-}
module Main where

import Control.Monad.ST

data R a b = R { x :: a , x :: b}

unsafeCoerce :: a -> b
unsafeCoerce i = case (R False False){x = i} of
  R a b -> b

unsafePerformIO :: IO a -> a
unsafePerformIO x = runST (unsafeCoerce x)

main = do
  let !() = unsafePerformIO $ putStrLn "Launching missiles..."
  pure ()