projects
/
ghc-base.git
/ blobdiff
commit
grep
author
committer
pickaxe
?
search:
re
summary
|
shortlog
|
log
|
commit
|
commitdiff
|
tree
raw
|
inline
| side by side
Fix some URLs
[ghc-base.git]
/
Data
/
STRef.hs
diff --git
a/Data/STRef.hs
b/Data/STRef.hs
index
81b1351
..
10853be
100644
(file)
--- a/
Data/STRef.hs
+++ b/
Data/STRef.hs
@@
-6,9
+6,9
@@
--
-- Maintainer : libraries@haskell.org
-- Stability : experimental
--
-- Maintainer : libraries@haskell.org
-- Stability : experimental
--- Portability : non-portable (requires non-portable module ST)
+-- Portability : non-portable (uses Control.Monad.ST)
--
--
--- Mutable references in the ST monad.
+-- Mutable references in the (strict) ST monad.
--
-----------------------------------------------------------------------------
--
-----------------------------------------------------------------------------
@@
-24,10
+24,18
@@
module Data.STRef (
import Prelude
#ifdef __GLASGOW_HASKELL__
import Prelude
#ifdef __GLASGOW_HASKELL__
+import GHC.ST
import GHC.STRef
#endif
import GHC.STRef
#endif
-import Data.Dynamic
+#ifdef __HUGS__
+import Hugs.ST
+import Data.Typeable
-#include "Dynamic.h"
+#include "Typeable.h"
INSTANCE_TYPEABLE2(STRef,stRefTc,"STRef")
INSTANCE_TYPEABLE2(STRef,stRefTc,"STRef")
+#endif
+
+-- |Mutate the contents of an 'STRef'
+modifySTRef :: STRef s a -> (a -> a) -> ST s ()
+modifySTRef ref f = writeSTRef ref . f =<< readSTRef ref