Control.Object.Instance

Instantiation

type Instance f g = MVar (Object f g)

new :: MonadIO m => Object f g -> m (Instance f g)

Create a new instance. This can be used inside unsafePerformIO to create top-level instances.

newSettle :: MonadIO m => Object f m -> m (Instance f m)

Create a new instance, having it sitting on the current environment.

Invocation

invokeOnUsing :: (MonadIO m, MonadMask m) => (Object f g -> t a -> g (a, Object f g)) -> (forall x. g x -> m x) -> Instance f g -> t a -> m a

invokeOn :: (MonadIO m, MonadMask m) => (forall x. g x -> m x) -> Instance f g -> f a -> m a

Invoke a method with an explicit landing function. In case of exception, the original object will be set.

(.-) :: (MonadIO m, MonadMask m) => Instance f m -> f a -> m a infixr 3

Invoke a method.

(..-) :: (MonadIO m, MonadMask m) => Instance t m -> Skeleton t a -> m a infixr 3

(?-) :: (MonadIO m, MonadMask m) => Instance f m -> f a -> m (Maybe a)

Try to invoke a method. If the instance is unavailable, it returns Nothing.