testsuite/tests/deriving/should_compile/T18914.hs


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{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE RankNTypes #-}
module T18914 where

type T f = forall a. f a

class C f where
  m1 :: T f
  m2 :: forall a. f a

newtype N f a = MkN (f a)
  deriving C