6 files changed, 26 insertions, 10 deletions
diff --git a/libraries/base/GHC/Base.lhs b/libraries/base/GHC/Base.lhs
index 70f589729e..d8eb3e690f 100644
--- a/libraries/base/GHC/Base.lhs
+++ b/libraries/base/GHC/Base.lhs
@@ -505,6 +505,19 @@ when    :: (Monad m) => Bool -> m () -> m ()
 {-# SPECIALISE when :: Bool -> Maybe () -> Maybe () #-}
 when p s                = if p then s else return ()
 
+-- | Evaluate each action in the sequence from left to right,
+-- and collect the results.
+sequence :: Monad m => [m a] -> m [a]
+{-# INLINE sequence #-}
+sequence ms = foldr k (return []) ms
+            where
+              k m m' = do { x <- m; xs <- m'; return (x:xs) }
+
+-- | @'mapM' f@ is equivalent to @'sequence' . 'map' f@.
+mapM :: Monad m => (a -> m b) -> [a] -> m [b]
+{-# INLINE mapM #-}
+mapM f as       =  sequence (map f as)
+
 -- | Promote a function to a monad.
 liftM   :: (Monad m) => (a1 -> r) -> m a1 -> m r
 liftM f m1              = do { x1 <- m1; return (f x1) }
diff --git a/libraries/base/GHC/Event/Manager.hs b/libraries/base/GHC/Event/Manager.hs
index ea49c0d8cb..20413792db 100644
--- a/libraries/base/GHC/Event/Manager.hs
+++ b/libraries/base/GHC/Event/Manager.hs
@@ -52,8 +52,9 @@ module GHC.Event.Manager
 import Control.Concurrent.MVar (MVar, newMVar, readMVar, putMVar,
                                 tryPutMVar, takeMVar, withMVar)
 import Control.Exception (onException)
-import Control.Monad (forM_, replicateM, void)
 import Data.Bits ((.&.))
+import Data.Foldable (forM_)
+import Data.Functor (void)
 import Data.IORef (IORef, atomicModifyIORef', mkWeakIORef, newIORef, readIORef,
                    writeIORef)
 import Data.Maybe (maybe)
@@ -61,7 +62,7 @@ import GHC.Arr (Array, (!), listArray)
 import GHC.Base
 import GHC.Conc.Signal (runHandlers)
 import GHC.Conc.Sync (yield)
-import GHC.List (filter)
+import GHC.List (filter, replicate)
 import GHC.Num (Num(..))
 import GHC.Real (fromIntegral)
 import GHC.Show (Show(..))
@@ -192,6 +193,8 @@ newWith oneShot be = do
   registerControlFd mgr (controlReadFd ctrl) evtRead
   registerControlFd mgr (wakeupReadFd ctrl) evtRead
   return mgr
+  where
+    replicateM n x = sequence (replicate n x)
 
 failOnInvalidFile :: String -> Fd -> IO Bool -> IO ()
 failOnInvalidFile loc fd m = do
diff --git a/libraries/base/GHC/Event/Thread.hs b/libraries/base/GHC/Event/Thread.hs
index 6fe76895ad..482e41f172 100644
--- a/libraries/base/GHC/Event/Thread.hs
+++ b/libraries/base/GHC/Event/Thread.hs
@@ -16,14 +16,14 @@ module GHC.Event.Thread
     ) where
 
 import Control.Exception (finally, SomeException, toException)
-import Control.Monad (forM, forM_, sequence_, zipWithM)
+import Data.Foldable (forM_, mapM_, sequence_)
 import Data.IORef (IORef, newIORef, readIORef, writeIORef)
 import Data.Tuple (snd)
 import Foreign.C.Error (eBADF, errnoToIOError)
 import Foreign.C.Types (CInt(..), CUInt(..))
 import Foreign.Ptr (Ptr)
 import GHC.Base
-import GHC.List (zipWith3)
+import GHC.List (zipWith, zipWith3)
 import GHC.Conc.Sync (TVar, ThreadId, ThreadStatus(..), atomically, forkIO,
                       labelThread, modifyMVar_, withMVar, newTVar, sharedCAF,
                       getNumCapabilities, threadCapability, myThreadId, forkOn,
@@ -99,15 +99,16 @@ closeFdWith :: (Fd -> IO ())        -- ^ Action that performs the close.
 closeFdWith close fd = do
   eventManagerArray <- readIORef eventManager
   let (low, high) = boundsIOArray eventManagerArray
-  mgrs <- forM [low..high] $ \i -> do
+  mgrs <- flip mapM [low..high] $ \i -> do
     Just (_,!mgr) <- readIOArray eventManagerArray i
     return mgr
   mask_ $ do
-    tables <- forM mgrs $ \mgr -> takeMVar $ M.callbackTableVar mgr fd
+    tables <- flip mapM mgrs $ \mgr -> takeMVar $ M.callbackTableVar mgr fd
     cbApps <- zipWithM (\mgr table -> M.closeFd_ mgr table fd) mgrs tables
     close fd `finally` sequence_ (zipWith3 finish mgrs tables cbApps)
   where
     finish mgr table cbApp = putMVar (M.callbackTableVar mgr fd) table >> cbApp
+    zipWithM f xs ys = sequence (zipWith f xs ys)
 
 threadWait :: Event -> Fd -> IO ()
 threadWait evt fd = mask_ $ do
@@ -244,7 +245,7 @@ startIOManagerThreads =
   withMVar ioManagerLock $ \_ -> do
     eventManagerArray <- readIORef eventManager
     let (_, high) = boundsIOArray eventManagerArray
-    forM_ [0..high] (startIOManagerThread eventManagerArray)
+    mapM_ (startIOManagerThread eventManagerArray) [0..high]
     writeIORef numEnabledEventManagers (high+1)
 
 show_int :: Int -> String
diff --git a/libraries/base/GHC/Event/TimerManager.hs b/libraries/base/GHC/Event/TimerManager.hs
index bac4685d94..bf6339a4d8 100644
--- a/libraries/base/GHC/Event/TimerManager.hs
+++ b/libraries/base/GHC/Event/TimerManager.hs
@@ -39,7 +39,7 @@ module GHC.Event.TimerManager
 -- Imports
 
 import Control.Exception (finally)
-import Control.Monad (sequence_)
+import Data.Foldable (sequence_)
 import Data.IORef (IORef, atomicModifyIORef', mkWeakIORef, newIORef, readIORef,
                    writeIORef)
 import GHC.Base
diff --git a/libraries/base/GHC/ForeignPtr.hs b/libraries/base/GHC/ForeignPtr.hs
index fe7293e41e..7943ef44d6 100644
--- a/libraries/base/GHC/ForeignPtr.hs
+++ b/libraries/base/GHC/ForeignPtr.hs
@@ -44,8 +44,8 @@ module GHC.ForeignPtr
         finalizeForeignPtr
   ) where
 
-import Control.Monad    ( sequence_ )
 import Foreign.Storable
+import Data.Foldable    ( sequence_ )
 import Data.Typeable
 
 import GHC.Show
diff --git a/libraries/base/GHC/IO/Handle.hs b/libraries/base/GHC/IO/Handle.hs
index 776618121f..5a8d570642 100644
--- a/libraries/base/GHC/IO/Handle.hs
+++ b/libraries/base/GHC/IO/Handle.hs
@@ -68,7 +68,6 @@ import GHC.Num
 import GHC.Real
 import Data.Maybe
 import Data.Typeable
-import Control.Monad ( mapM )
 
 -- ---------------------------------------------------------------------------
 -- Closing a handle