{-# LANGUAGE KindSignatures #-} module WCompatWarningsOnOff where import qualified Data.Semigroup as Semi (<>) = undefined -- Semigroup warnings -- -fwarn-noncanonical-monoid-instances newtype S = S Int instance Semi.Semigroup S where (<>) = mappend instance Monoid S where S a `mappend` S b = S (a+b) mempty = S 0 -- -fwarn-star-is-type b :: (Bool :: *) b = True