Add usefull instances for Async

distributed-process-async.cabal

@@ -42,11 +42,6 @@ library
                    stm >= 2.4 && < 2.5,
                    time > 1.4 && < 1.6,
                    transformers
-  if impl(ghc <= 7.5)
-    Build-Depends:   template-haskell == 2.7.0.0,
-                     derive == 2.5.5,
-                     uniplate == 1.6.12,
-                     ghc-prim
   extensions:      CPP
                    InstanceSigs
   hs-source-dirs:   src

src/Control/Distributed/Process/Async.hs

@@ -59,10 +59,6 @@ module Control.Distributed.Process.Async
   , waitBoth
   ) where
 
-#if ! MIN_VERSION_base(4,6,0)
-import Prelude hiding (catch)
-#endif
-
 import Control.Applicative
 import Control.Concurrent.STM hiding (check)
 import Control.Distributed.Process
@@ -74,6 +70,7 @@ import Data.Maybe
   )
 
 import System.Timeout (timeout)
+import Prelude
 
 -- | Wraps a regular @Process a@ as an 'AsyncTask'.
 task :: Process a -> AsyncTask a

src/Control/Distributed/Process/Async/Internal/Types.hs

@@ -4,6 +4,7 @@
 {-# LANGUAGE RankNTypes                #-}
 {-# LANGUAGE ExistentialQuantification #-}
 {-# LANGUAGE DeriveGeneric             #-}
+{-# LANGUAGE DeriveFunctor             #-}
 
 -- | shared, internal types for the Async package
 module Control.Distributed.Process.Async.Internal.Types
@@ -23,6 +24,7 @@ import Control.Distributed.Process.Serializable
   )
 import Data.Binary
 import Data.Typeable (Typeable)
+import Data.Monoid
 
 import GHC.Generics
 
@@ -40,11 +42,14 @@ data Async a = Async {
     _asyncWorker  :: AsyncRef
   , _asyncMonitor :: AsyncRef
   , _asyncWait    :: STM (AsyncResult a)
-  }
+  } deriving (Functor)
 
 instance Eq (Async a) where
   Async a b _ == Async c d _  =  a == c && b == d
 
+instance Ord (Async a) where
+  compare (Async a b _) (Async c d _) = a `compare` c <> b `compare` d
+
 -- | A task to be performed asynchronously.
 data AsyncTask a =
     AsyncTask {
@@ -67,7 +72,8 @@ data AsyncResult a =
   | AsyncLinkFailed DiedReason  -- ^ a link failure and the reason
   | AsyncCancelled              -- ^ a cancelled action
   | AsyncPending                -- ^ a pending action (that is still running)
-    deriving (Typeable, Generic)
+    deriving (Typeable, Generic, Functor)
+
 
 instance Serializable a => Binary (AsyncResult a) where