改行でstring分割

Lines.hs

lines' :: String -> [String]
lines' s = go id s
  where
    go ac []             = [ac ""]
    go ac ('\r':'\n':cs) = ac "" : go id cs
    go ac ('\r'     :cs) = ac "" : go id cs
    go ac (     '\n':cs) = ac "" : go id cs
    go ac (        c:cs) = go (ac . (c:)) cs