textBot :: (Text -> Maybe Text) -> SlackBot ()
textBot f (Message cid _ msg _ _ _)
  | (Just response) <- f msg = sendMessage cid response
textBot :: (Text -> Maybe Text) -> SlackBot ()
textBot f (Message cid _ msg _ _ _)
  | (Just response) <- f msg = sendMessage cid response
textBot f (Message cid _ msg _ _ _)
  | (Just response) <- f msg = sendMessage cid response