Removing parts of an infinite list

Foo.hs

-- http://stackoverflow.com/questions/13026095/lack-of-understanding-infinite-lists-and-seq-operator
module Main
       where

main :: IO ()
main = print (take 100 (foo 2 [1..]))

foo :: Int -> [a] -> [a]
foo n l  = go l
  where
    go xs = let (toKeep, rest) = splitAt n xs
            in toKeep ++ go (drop n rest)