foreign-var 0.0.0.1 → 0.1

raw patch · 3 files changed

+13/−53 lines, 3 filesPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

Files

• CHANGELOG.markdown +4/−0
• foreign-var.cabal +1/−1
• src/Foreign/Var.hs +8/−52

@@ -1,3 +1,7 @@+0.1+---+* Simplified `Var`+ 0.0.0.1 ------- * Enable compilation on GHC < 7.6

@@ -1,6 +1,6 @@ name:          foreign-var category:      FFI, Mutable State-version:       0.0.0.1+version:       0.1 license:       BSD3 cabal-version: >= 1.10 license-file:  LICENSE

@@ -17,8 +17,7 @@ module Foreign.Var   (   -- * Variables-    Var(..)-  , newVar+    Var(Var)   , mapVar   , SettableVar(SettableVar)   , GettableVar@@ -35,9 +34,6 @@ import Data.Typeable import Foreign.Ptr import Foreign.Storable---import Data.Void---import Data.Functor.Contravariant---import Data.Functor.Contravariant.Divisible  -------------------------------------------------------------------- -- * Var@@ -54,7 +50,7 @@ -- thrown exception: -- -- @--- do x <- 'getVar' v; 'setVar' v y; 'setVar' v x+-- do x <- 'get' v; v '$=' y; v '$=' x -- @ -- -- should restore the previous state.@@ -62,59 +58,21 @@ -- Ideally, in the absence of thrown exceptions: -- -- @--- 'setVar' v a >> 'getVar' v+-- v '$=' a >> 'get' v -- @ -- -- should return @a@, regardless of @a@. In practice some 'Var's only -- permit a very limited range of value assignments, and do not report failure.------ The result of 'updateVar' should also be compatible with the result of getting--- and setting separately, however, it may be more efficient or have better--- atomicity properties in a concurrent setting.-data Var a = Var-  { getVar :: IO a                  -- ^ Used by 'get'-  , updateVar  :: (a -> a) -> IO () -- ^ Used by @('$~')@-  , updateVar' :: (a -> a) -> IO () -- ^ Used by @('$~!')@-  , setVar :: a -> IO ()            -- ^ Used by @('$=')@-  } deriving Typeable---- | Build a 'Var' form a getter and a setter.-newVar :: (IO a)       -- ^ getter-       -> (a -> IO ()) -- ^ setter-       -> Var a-newVar g s = Var g u u' s where-  u f = do-    a <- g-    s (f a)-  u' f = do-    a <- g-    s $! f a+data Var a = Var (IO a) (a -> IO ()) deriving Typeable  -- | Change the type of a 'Var' mapVar :: (b -> a) -> (a -> b) -> Var a -> Var b-mapVar ba ab (Var ga ua ua' sa) = Var (ab <$> ga) (\bb -> ua (ba . bb . ab)) (\bb -> ua' (ba . bb . ab)) (sa . ba)+mapVar ba ab (Var ga sa) = Var (ab <$> ga) (sa . ba) {-# INLINE mapVar #-}  newtype SettableVar a = SettableVar (a -> IO ())   deriving Typeable -{--instance Contravariant SettableVar where-  contramap f (SettableVar k) = SettableVar (k . f)-  {-# INLINE contramap #-}--instance Divisible SettableVar where-  divide k (SettableVar l) (SettableVar r) = SettableVar $ \ a -> case k a of-    (b, c) -> l b >> r c-  conquer = SettableVar $ \_ -> return ()--instance Decidable SettableVar where-  lose k = SettableVar (absurd . k)-  choose k (SettableVar l) (SettableVar r) = SettableVar $ \ a -> case k a of-    Left b -> l b-    Right c -> r c--}- type GettableVar = IO  --------------------------------------------------------------------@@ -135,7 +93,7 @@   {-# INLINE ($=) #-}  instance HasSetter (Var a) a where-  Var _ _ _ s $= a = liftIO $ s a+  Var _ s $= a = liftIO $ s a  instance Storable a => HasSetter (Ptr a) a where   p $= a = liftIO $ poke p a@@ -166,9 +124,7 @@     a <- get r     r $=! f a -instance HasUpdate (Var a) a a where-  Var _ u _ _ $~  f = liftIO $ u f-  Var _ _ v _ $~! f = liftIO $ v f+instance HasUpdate (Var a) a a  instance Storable a => HasUpdate (Ptr a) a a @@ -198,7 +154,7 @@   get :: MonadIO m => t -> m a  instance HasGetter (Var a) a where-  get (Var g _ _ _) = liftIO g+  get (Var g _) = liftIO g  instance HasGetter (TVar a) a where   get = liftIO . atomically . readTVar