Int

x :: Type
x = _

x = Int

x = 5

x :: Type
x = x

forever :: Applicative f => f a -> f Type
forever x = x *> forever x

echo :: IO ()
echo = do
  x <- getLine
  putStrLn x

absurd :: forall a. Type -> a
absurd = \case

• Illegal visible, dependent quantification in the type of a term:
     forall b. forall k -> forall (a :: k). k -> b
   (GHC does not yet support this)