How to get every Nth element of an infinite list in Haskell?

Question

More specifically, how do I generate a new list of every Nth element from an existing infinite list?

E.g. if the list is [5, 3, 0, 1, 8, 0, 3, 4, 0, 93, 211, 0

Answer 1

It's more elegant to solve a related problem first: Keep every element whose index is divisible by n.

everyNth n [] = []
everyNth n (x:xs) = x : (everyNth n . drop (n-1)) xs

And then to solve the example, use

everyNthFirst n = everyNth n . drop (n-1)

everyNthFirst 3 [5, 3, 0, 1, 8, 0, 3, 4, 0, 93, 211, 0 ...] gives [0, 0, 0, ...]