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{-# LANGUAGE NoImplicitPrelude #-} module Test where import GHC.Base data U1 p = U1 instance Functor U1 where fmap f U1 = U1 instance Applicative U1 where pure _ = U1 U1 <*> U1 = U1 instance Alternative U1 where empty = U1 U1 <|> U1 = U1