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data A = True' | False'
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deriving Show
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foo :: A -> Integer
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foo True' = 1
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foo False' = 0
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data P3 = P Bool A -- P (Bool x A)
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data BigP = P1 Bool A | P2 Integer
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deriving Show
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bar :: BigP -> Integer
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bar (P1 _ _) = 1
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bar (P2 _) = 2
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int_plus_3 :: Integer -> Integer
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int_plus_3 n = n + 3
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-- examples
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comp :: BigP -> Integer
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comp = int_plus_3 . bar
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-- same as: int_plus_3 $ bar $ P2 10
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double_arg :: Integer -> Integer -> Integer
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double_arg a b = a + b
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partially_applied :: Integer -> Integer
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partially_applied = double_arg 7
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func_arg :: (Integer -> Integer) -> Integer -> Integer
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func_arg f b = f b
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main :: IO ()
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main = putStrLn "Hello world"
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