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{-# LANGUAGE GeneralizedNewtypeDeriving #-}
-- Tests newtype deriving with
-- a non-type constructor in the representation
module Main where
newtype Wrap m a = Wrap { unWrap :: m a }
deriving (Monad, Eq)
foo :: Int -> Wrap IO a -> Wrap IO ()
foo 0 a = return ()
foo n a = do { a; foo (n-1) a }
main = do { unWrap (foo 3 (Wrap (putChar 'x'))); putChar '\n' }
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