Haskell replace element in list

Question

Is there any built-in function to replace an element at a given index in haskell?

Example:

replaceAtIndex(2,\"foo\",[\"bar\",\"bar\",\"bar\"])

Answer 1

As far as I know (and can find) it does not exist by default. However, there exists splitAt in Data.List so:

replaceAtIndex n item ls = a ++ (item:b) where (a, (_:b)) = splitAt n ls

This is O(N) though. If you find yourself doing this a lot, look at another datatype such as array.