在以下情况下，我可以在initCass' fdsEnv MonadUnliftIO m块中直接使用RIO（类型为do）：

initCass :: RIO FdsEnv ClientState
initCass = do
  fdsEnv <- ask
  initCass' fdsEnv

initCass' :: MonadUnliftIO m => FdsEnv -> m ClientState
initCass' fdsEnv = do
  let config = fdsConfig fdsEnv
  let logger = fdsLogger fdsEnv
  initCassandra (dbName config) (dbHost config) (dbPort config) logger

但是，当我尝试在此处执行类似操作时：

runClientSafe :: MonadUnliftIO m => (ClientState -> m a) -> RIO FdsEnv a
runClientSafe cliFun = do
  fdsEnv <- ask
  bracket (runRIO fdsEnv initCass) shutdown cliFun

我得到一个错误：

    • Couldn't match type ‘m’ with ‘RIO FdsEnv’
      ‘m’ is a rigid type variable bound by
        the type signature for:
          runClientSafe :: forall (m :: * -> *) a.
                           MonadUnliftIO m =>
                           (ClientState -> m a) -> RIO FdsEnv a
        at src/FDS/Database/Cassandra.hs:75:1-72
      Expected type: RIO FdsEnv a
        actual type: m a
    • In a stmt of a 'do' block:
        bracket (runRIO fdsEnv initCass) shutdown cliFun
      In the expression:
        do fdsEnv <- ask
           bracket (runRIO fdsEnv initCass) shutdown cliFun
      In an equation for ‘runClientSafe’:
          runClientSafe cliFun
            = do fdsEnv <- ask
                 bracket (runRIO fdsEnv initCass) shutdown cliFun
    • Relevant bindings include
        cliFun :: ClientState -> m a
          (bound at src/FDS/Database/Cassandra.hs:76:15)
        runClientSafe :: (ClientState -> m a) -> RIO FdsEnv a
          (bound at src/FDS/Database/Cassandra.hs:76:1)
   |
78 |   bracket (runRIO fdsEnv initCass) shutdown cliFun
   |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

我认为差异在于，在第一种情况下，initCass'的m解析为RIO FdsEnv，所以这是有道理的。我想真正需要的是一种从MonadUnliftIO m -> RIO e开始的方法，但不确定是否可行。