Guards vs. if-then-else vs. cases in Haskell

Question

I have three functions that find the nth element of a list:

nthElement :: [a] -> Int -> Maybe a 
nthElement [] a = Nothing
nthElement (x:xs) a | a <= 0          


        

Answer 1

I know this is question about style for explicitly recursive functions, but I would suggest that the best style is finding a way to reuse existing recursive functions instead.

nthElement xs n = guard (n > 0) >> listToMaybe (drop (n-1) xs)