25 lines
709 B
TeX
25 lines
709 B
TeX
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And now you can chain functions together. Not just two! Look:
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\begin{haskellcode}
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f :: String -> Bool
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f xs = (even . length . (\x -> x ++ "Hello world")) xs
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-- or less ugly
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f xs = even . length . (\x -> x ++ "Hello world") $ xs
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\end{haskellcode}
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% $
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\pause
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Another example where currying is actually important:
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\begin{haskellcode}
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f :: Int -> Bool
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f x = even . (+) 3 . (-) 4 $ x
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-- why not this?
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f x = even . (+) 3 . (-) $ 4 x
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\end{haskellcode}
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%$
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\pause
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So there are a few things that we have to be aware of:
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\begin{itemize}
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\item the types have to fit!
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\item the arity has to fit!
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\end{itemize}
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That sounds complicated at first, because it counts for the whole composition chain. But you'll get used to it.
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