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Haskell 在ResourceT上的Conduit中提升monad IO_Haskell_Conduit - Fatal编程技术网

Haskell 在ResourceT上的Conduit中提升monad IO

Haskell 在ResourceT上的Conduit中提升monad IO,haskell,conduit,Haskell,Conduit,我正在尝试使用函数MergeSources,其中具有以下签名: mergeSources :: (MonadResource mi, MonadIO mo, MonadUnliftIO mi) => [ConduitT () a mi ()] -- ^ The sources to merge. -> Int -- ^ The bound of the intermediate channel. ->

我正在尝试使用函数MergeSources,其中具有以下签名:

mergeSources :: (MonadResource mi, MonadIO mo, MonadUnliftIO mi)
             => [ConduitT () a mi ()] -- ^ The sources to merge.
             -> Int -- ^ The bound of the intermediate channel.
             -> mo (ConduitT () a mi ())    
我有直接基于IO的资料来源,我不知道如何处理这个mi Monad,我相信ResourceT是候选人:

因此,我有以下签名的来源:

ConduitT () (Connection,WorkspaceId) IO ()
我想要这个签名:

ConduitT () (Connection,WorkspaceId) (ResourceT IO) ()
尽管在这些操作中我没有资源可以处理(我有一个连接,但它是全局的,这是他们推荐的…),我还是给你一个我想要使用的函数的例子

streamAllWorkspaceAlreadyCreated :: Connection -> ConduitT () (Connection,WorkspaceId) IO ()
streamAllWorkspaceAlreadyCreated  eventStoreConnection = do
    yield eventStoreConnection
    .| WorkspaceStream.streamAll
    .| WorkspaceStream.discardCorruptedStreams
    .| mapC (\workSpaceId -> (eventStoreConnection,workSpaceId))

运输管道怎么样

transPipe :: Monad m => (forall a. m a -> n a) -> ConduitT i o m r -> ConduitT i o n r

transPipe liftIO :: ConduitT i o IO r -> ConduitT i o (ResourceT IO) r