@@ -116,6 +116,9 @@ module Prelude
116116 class Functor f where
117117 (<$>) :: forall a b. (a -> b) -> f a -> f b
118118
119+ void :: forall f a. (Functor f) => f a -> f {}
120+ void fa = const {} <$> fa
121+
119122 infixl 4 <*>
120123
121124 class (Functor f) <= Apply f where