testsuite/tests/typecheck/should_fail/T2994.hs


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{-# LANGUAGE Haskell2010 #-}
{-# LANGUAGE MultiParamTypeClasses #-}

-- #2994

module T2994 where

class MonadReader a b 

newtype Reader' r a = Reader' (r -> a)

instance MonadReader Int

instance MonadReader (Reader' r)

instance MonadReader r r (Reader' r)