{-# LANGUAGE ExistentialQuantification #-}

class Device a

data Device' = forall a.(Device a, Show a)=> MakeDevice' a

data Hedgehog = Hedgehog
	deriving (Show)

data GrassSnake = GrassSnake
	deriving (Show)

instance Device Hedgehog
instance Device GrassSnake

device :: String -> Device'
device "Уж" = MakeDevice' Hedgehog
device "Ёж" = MakeDevice' GrassSnake

main = putStrLn $ f $ device "Уж"
	where f (MakeDevice' a) = show a