ugly parser

matchAttribute : Parser
matchAttribute s = let chars = unpack s in
                       case chars of
                            [] => Left s
                            (c :: cs) => if isAlpha c
                                            then let parsed = pack (c :: takeWhile isAlphaNumOrDash cs) in
                                                     Right (drop (length parsed) s, MkElement parsed [] [])
                                            else Left s