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Is it possible to cast an Integer to an Int? The other direction is possible: toInteger. I know that Integer is able to store bigger values, but sometimes a conversation is needed to use functions in the standard library. I tried (n :: Int) and other code samples I found - but nothing works.
takeN :: Integer -> [a] -> [a] takeN n l = take n l 
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To convert the Integer to int, we can use the intValue() or the parseInt() method.
fromInteger :: Num a => Integer -> a. as well as for converting to Integer s: toInteger:: Integral a => a -> Integer.
It states that this function is of type Int -> Int , that is to say, it takes an integer as its argument and it returns an integer as its value.
What's the difference between Integer and Int ? Integer can represent arbitrarily large integers, up to using all of the storage on your machine. Int can only represent integers in a finite range.
Use fromIntegral.
takeN :: Integer -> [a] -> [a] takeN n l = take (fromIntegral n) l Note that fromIntegral :: (Integral a, Num b) => a -> b, so sometimes you will need an extra type annotation (e.g. (fromIntegral n :: Int)), but usually the compiler can infer which type you want.
In the special case of your example, in Data.List there is genericTake :: (Integral i) => i -> [a] -> [a], which does the same thing as take but with a more general type.
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