-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Generic Mutable Ref Abstraction Layer
--   
--   Ref is a generic layer over mutable references, currently only IO and
--   ST refs. Future extensions may include a generic api for shared state
--   concurrency.
@package ref
@version 0.1.1.2

module Data.Ref.CAS

-- | Performs a machine-level compare and swap operation on an
--   <a>STRef</a>. Returns a tuple containing a <a>Bool</a> which is
--   <a>True</a> when a swap is performed, along with the <tt>current</tt>
--   value from the <a>STRef</a>.
--   
--   Note "compare" here means pointer equality in the sense of
--   <a>reallyUnsafePtrEquality#</a>.
casSTRef :: STRef s a -> a -> a -> ST s (Bool, a)

-- | Performs a machine-level compare and swap operation on an
--   <a>IORef</a>. Returns a tuple containing a <a>Bool</a> which is
--   <a>True</a> when a swap is performed, along with the <tt>current</tt>
--   value from the <a>IORef</a>.
--   
--   Note "compare" here means pointer equality in the sense of
--   <a>reallyUnsafePtrEquality#</a>.
casIORef :: IORef a -> a -> a -> IO (Bool, a)

module Data.Ref
class Ref ref where type family RefM ref :: * -> *
newRef :: Ref ref => a -> RefM ref (ref a)
newRef' :: Ref ref => a -> RefM ref (ref a)
readRef :: Ref ref => ref a -> RefM ref a
readRef' :: Ref ref => ref a -> RefM ref a
writeRef :: Ref ref => ref a -> a -> RefM ref ()
writeRef' :: Ref ref => ref a -> a -> RefM ref ()
modifyRef :: Ref ref => ref a -> (a -> a) -> RefM ref ()
modifyRef' :: Ref ref => ref a -> (a -> a) -> RefM ref ()
instance Ref (STRef s)
instance Ref IORef