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Equivalent function compositions

example

code:

main :: IO ()
main = 
    do
        print $ f f1 f2 f3 6.4
        print $ f' f1 f2 f3 6.4
        print $ f'' f1 f2 f3 6.4
 
f :: ((Integer -> String) -> Double -> [String]) -> (Int -> String) -> (Integer -> Int) ->  Double -> [String]
f f1' f2' f3' x' = f1' (f2' . f3') x'
 
f' :: ((Integer -> String) -> Double -> [String]) -> (Int -> String) -> (Integer -> Int) ->  Double -> [String]
f' f1' f2' f3' = f1' (f2' . f3')
 
f'' :: ((Integer -> String) -> Double -> [String]) -> (Int -> String) -> (Integer -> Int) ->  Double -> [String]
f'' f1' f2' = f1' . (f2' . )
 
f1 :: (Integer -> String) -> Double -> [String] -- (a -> c) -> x -> r
f1 fx nd = [(fx (floor nd))]
f2 :: (Int -> String) -- (b -> c)
f2 n = replicate n 'x'
f3 :: (Integer -> Int) -- (a -> b)
f3 n = fromIntegral n

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