0

每当我尝试使用 newtypes 编译 haskell 程序时，我都会收到一条错误消息，指出“No instance for blah blah from the use of ...”，例如：

No instance for (Hashable NT.EndPointAddress)
  arising from a use of `hashable-1.2.0.10:Data.Hashable.Class.$gdmhashWithSalt'
Possible fix:
  add an instance declaration for (Hashable NT.EndPointAddress)
In the expression:
  (hashable-1.2.0.10:Data.Hashable.Class.$gdmhashWithSalt)
In an equation for `hashWithSalt':
    hashWithSalt
      = (hashable-1.2.0.10:Data.Hashable.Class.$gdmhashWithSalt)
In the instance declaration for `Hashable NodeId'

谁能建议可能发生的事情？

谢谢，

卡尔

我添加了与上述错误消息相关的代码。它张贴在下面。错误发生在第 132 行。代码来自 Types.hs，它来自发布在 github 上的分布式进程的开发分支。对于我尝试编译的任何包含新类型的代码，我都会遇到同样的错误。

{-# LANGUAGE DeriveGeneric #-}

-- | Types used throughout the Cloud Haskell framework
--
-- We collect all types used internally in a single module because
-- many of these data types are mutually recursive and cannot be split across
-- modules.
module Control.Distributed.Process.Internal.Types
  ( -- * Node and process identifiers
    NodeId(..)
  , LocalProcessId(..)
  , ProcessId(..)
  , Identifier(..)
  , nodeOf
  , firstNonReservedProcessId
  , nullProcessId
    -- * Local nodes and processes
  , LocalNode(..)
  , Tracer(..)
  , LocalNodeState(..)
  , LocalProcess(..)
  , LocalProcessState(..)
  , Process(..)
  , runLocalProcess
  , ImplicitReconnect(..)
    -- * Typed channels
  , LocalSendPortId
  , SendPortId(..)
  , TypedChannel(..)
  , SendPort(..)
  , ReceivePort(..)
    -- * Messages
  , Message(..)
  , isEncoded
  , createMessage
  , createUnencodedMessage
  , unsafeCreateUnencodedMessage
  , messageToPayload
  , payloadToMessage
    -- * Node controller user-visible data types
  , MonitorRef(..)
  , ProcessMonitorNotification(..)
  , NodeMonitorNotification(..)
  , PortMonitorNotification(..)
  , ProcessExitException(..)
  , ProcessLinkException(..)
  , NodeLinkException(..)
  , PortLinkException(..)
  , ProcessRegistrationException(..)
  , DiedReason(..)
  , DidUnmonitor(..)
  , DidUnlinkProcess(..)
  , DidUnlinkNode(..)
  , DidUnlinkPort(..)
  , SpawnRef(..)
  , DidSpawn(..)
  , WhereIsReply(..)
  , RegisterReply(..)
  , ProcessInfo(..)
  , ProcessInfoNone(..)
    -- * Node controller internal data types
  , NCMsg(..)
  , ProcessSignal(..)
    -- * Accessors
  , localProcesses
  , localPidCounter
  , localPidUnique
  , localConnections
  , localProcessWithId
  , localConnectionBetween
  , monitorCounter
  , spawnCounter
  , channelCounter
  , typedChannels
  , typedChannelWithId
    -- * Utilities
  , forever'
  ) where

import System.Mem.Weak (Weak)
import Data.Map (Map)
import Data.Int (Int32)
import Data.Typeable (Typeable, typeOf)
import Data.Binary (Binary(put, get), putWord8, getWord8, encode)
import qualified Data.ByteString as BSS (ByteString, concat, copy)
import qualified Data.ByteString.Lazy as BSL
  ( ByteString
  , toChunks
  , splitAt
  , fromChunks
  , length
  )
import qualified Data.ByteString.Lazy.Internal as BSL (ByteString(..))
import Data.Accessor (Accessor, accessor)
import Control.Category ((>>>))
import Control.DeepSeq (NFData(..))
import Control.Exception (Exception)
import Control.Concurrent (ThreadId)
import Control.Concurrent.Chan (Chan)
import Control.Concurrent.STM (STM)
import qualified Network.Transport as NT (EndPoint, EndPointAddress, Connection)
import Control.Applicative (Applicative, Alternative, (<$>), (<*>))
import Control.Monad.Reader (MonadReader(..), ReaderT, runReaderT)
import Control.Monad.IO.Class (MonadIO)
import Control.Distributed.Process.Serializable
  ( Fingerprint
  , Serializable
  , fingerprint
  , encodeFingerprint
  , sizeOfFingerprint
  , decodeFingerprint
  , showFingerprint
  )
import Control.Distributed.Process.Internal.CQueue (CQueue)
import Control.Distributed.Process.Internal.StrictMVar (StrictMVar)
import Control.Distributed.Process.Internal.WeakTQueue (TQueue)
import Control.Distributed.Static (RemoteTable, Closure)
import qualified Control.Distributed.Process.Internal.StrictContainerAccessors as DAC (mapMaybe)

import Data.Hashable
import GHC.Generics

--------------------------------------------------------------------------------
-- Node and process identifiers                                               --
--------------------------------------------------------------------------------

-- | Node identifier
newtype NodeId = NodeId { nodeAddress :: NT.EndPointAddress }
  deriving (Eq, Ord, Typeable, Generic)
instance Binary NodeId where
instance NFData NodeId
instance Hashable NodeId where
instance Show NodeId where
  show (NodeId addr) = "nid://" ++ show addr

-- | A local process ID consists of a seed which distinguishes processes from
-- different instances of the same local node and a counter
data LocalProcessId = LocalProcessId
  { lpidUnique  :: {-# UNPACK #-} !Int32
  , lpidCounter :: {-# UNPACK #-} !Int32
  }
  deriving (Eq, Ord, Typeable, Generic, Show)
4

2 回答 2

1

好的，想通了。EndPointAddress 在 hashable 的 master 分支中没有实例。为了成功编译分布式进程平台，我必须下载以下软件包的开发分支：

hashable
distributed-process
distributed-process-static
rank1dynamic
network-transport
network-transport-tcp
distributed-process-simplelocalnet
distributed-process-platform

我在以下线程编译分布式进程中找到了此信息

感谢您花时间回复我的帖子！

于 2013-07-27T16:22:16.440 回答
0

看起来您安装了多个版本hashable。使用ghc-pkg list,ghc-pkg unregister等来找出发生了什么并修复它。几乎可以肯定，您只想拥有一个版本的hashable.

于 2013-07-26T03:28:09.007 回答