isPasswordRightLength :: [Char] -> Either.Either [Char] [Char]
isPasswordRightLength pwd =
  let len = length pwd
      in
      if len >= 6 && len <= 16
         then Right pwd
         else Left ("the length " ++ (show len) ++ " is not right")
isPasswordRightLength :: [Char] -> Either.Either [Char] [Char]
isPasswordRightLength pwd =
  let len = length pwd
      in
      if len >= 6 && len <= 16
         then Right pwd
         else Left ("the length " ++ (show len) ++ " is not right")
isPasswordRightLength pwd =
  let len = length pwd
      in
      if len >= 6 && len <= 16
         then Right pwd
         else Left ("the length " ++ (show len) ++ " is not right")