import Data.List (unfoldr)

-- *Main> split ',' ",,,abc,bd,,ce,,,"
-- ["abc","bd","ce"]

genericSplit :: (a -> Bool) -> [a] -> [[a]]
genericSplit p xs = unfoldr (splitOne p) xs
    where
       splitOne _ [] = Nothing
       splitOne p (x:xs) | p x = splitOne p xs
       splitOne p xs = Just (before, after)
           where (before, afterIncluding) = span (not.p) xs
                 after = dropWhile p afterIncluding

split s xs = genericSplit (==s) xs