diff options
Diffstat (limited to 'libraries/base/Data/IORef.hs')
| -rw-r--r-- | libraries/base/Data/IORef.hs | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/libraries/base/Data/IORef.hs b/libraries/base/Data/IORef.hs index 1b4b110293..70ea4b1550 100644 --- a/libraries/base/Data/IORef.hs +++ b/libraries/base/Data/IORef.hs @@ -1,3 +1,4 @@ +{-# OPTIONS_GHC -XNoImplicitPrelude #-} ----------------------------------------------------------------------------- -- | -- Module : Data.IORef @@ -27,14 +28,12 @@ module Data.IORef #endif ) where -import Prelude -- Explicit dependency helps 'make depend' do the right thing - #ifdef __HUGS__ import Hugs.IORef #endif #ifdef __GLASGOW_HASKELL__ -import GHC.Base ( mkWeak#, atomicModifyMutVar# ) +import GHC.Base import GHC.STRef import GHC.IOBase #if !defined(__PARALLEL_HASKELL__) @@ -61,7 +60,7 @@ mkWeakIORef r@(IORef (STRef r#)) f = IO $ \s -> -- |Mutate the contents of an 'IORef' modifyIORef :: IORef a -> (a -> a) -> IO () -modifyIORef ref f = writeIORef ref . f =<< readIORef ref +modifyIORef ref f = readIORef ref >>= writeIORef ref . f -- |Atomically modifies the contents of an 'IORef'. |