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PODifficulty in Haskell with recursive tuple function
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copied!<p>I have a small program that reads in a file and processes the data into a custom data type. The file being read contains lines of data that look like this:</p> <pre><code>cat 10 20 dog hamster 12 2 wombat monkey 1 9 zebra lion 30 60 rhino ... </code></pre> <p>My program to process the file looks like this:</p> <pre><code>main :: IO () main = do contents <- readFile "myfile.xyz" let process = clean contents let f = processFile process print f clean :: String -> [[String]] clean x = Prelude.map words $ lines x processFile :: [[String]] -> [(XyzData)] processFile [[a,b,c,d]] = [(XyzData a (read b :: Int) (read c :: Int) d)] processFile (x:xs) = processFile xs data XyzData = XyzData { animal1 :: String, number1 :: Int, number2 :: Int, animal2 :: String } deriving (Show) </code></pre> <p>My problem is with the <code>processFile</code> function. Currently, this function only captures the last line of the file and prints it to the screen. I am confused on how to implement recursion with a tuple instead of using append with a list in this function. Can anyone show me how how to fix my function and/or a better implementation of this function? The printed output of this program should be:</p> <pre><code>[XyzData {animal1 = "cat", number1 = 10, number2 = 20, animal2 = "dog"}, [XyzData {animal1 = "hampster", number1 = 12, number2 = 2, animal2 = "wombat"}, [XyzData {animal1 = "monkey", number1 = 1, number2 = 9, animal2 = "zebra"}, [XyzData {animal1 = "lion", number1 = 30, number2 = 60, animal2 = "rhino"}] </code></pre> <p>Thanks for your time. </p>

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