maybeToEither :: a -> Maybe b -> Either a b
maybeToEither left m = case m of
  Just x -> Right x
  Nothing -> Left left

--TODO: use the correct callerID
maybeToEither :: a -> Maybe b -> Either a b
maybeToEither left m = case m of
  Just x -> Right x
  Nothing -> Left left

--TODO: use the correct callerID
maybeToEither left m = case m of
  Just x -> Right x
  Nothing -> Left left

--TODO: use the correct callerID