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


-- | Computational Effects
--   
--   An alternative to Monad Transformers.
@package effects
@version 0

module Control.Effects
data Handler e m a r
Handler :: (a -> m e) -> (e -> m r) -> Handler e m a r
ret :: Handler e m a r -> a -> m e
fin :: Handler e m a r -> e -> m r
with :: Monad m => Handler e m a r -> (Proxy (ContT e m) -> ContT e m a) -> m r
operation :: (m ~ (ContT r m'), AutoLift m n) => Proxy m -> ((a -> m' r) -> m' r) -> n a
run :: Cont a a -> a
runIO :: ContT () IO () -> IO ()
io :: AutoLift (ContT () IO) n => IO a -> n a
ioHandler :: Handler a IO a a

-- | Continuation monad. <tt>Cont r a</tt> is a CPS computation that
--   produces an intermediate result of type <tt>a</tt> within a CPS
--   computation whose final result type is <tt>r</tt>.
--   
--   The <tt>return</tt> function simply creates a continuation which
--   passes the value on.
--   
--   The <tt>&gt;&gt;=</tt> operator adds the bound function into the
--   continuation chain.
type Cont r = ContT r Identity

-- | The continuation monad transformer. Can be used to add continuation
--   handling to other monads.
data ContT r m :: (* -> *) a :: * -> (* -> *) -> * -> *
data Proxy m :: (* -> *)
class AutoLift m1 m2
instance AutoLift' m1 m2 m1 m2 => AutoLift m1 m2
instance AutoLift' m1 m2 n1 n2 => AutoLift' m1 m2 (ContT r1 n1) (ContT r2 n2)
instance (AutoLift' m1 m2 Identity n, Monad m2) => AutoLift' m1 (ContT r m2) Identity (ContT s n)
instance (AutoLift' m1 m2 IO n, Monad m2) => AutoLift' m1 (ContT r m2) IO (ContT s n)
instance m1 ~ m2 => AutoLift' m1 m2 Identity Identity
instance m1 ~ m2 => AutoLift' m1 m2 IO IO

module Control.Effects.Cont
shift :: (c ~ (ContT r m), AutoLift c n, Monad m) => Proxy c -> ((m a -> m r) -> m r) -> n a
reset :: Monad m => Handler a m a a

module Control.Effects.Either
throwEither :: (c ~ (ContT (m (Either e r)) m), AutoLift c n, Monad m) => Proxy c -> e -> n Void
catchEither :: Monad m => (e -> m a) -> Handler (m (Either e a)) m a a

module Control.Effects.Error
throwError :: (c ~ (ContT ((e -> m r) -> m r) m), AutoLift c n, Monad m) => Proxy c -> e -> n Void
catchError :: Monad m => (e -> m a) -> Handler ((e -> m a) -> m a) m a a

module Control.Effects.Set
choose :: (c ~ (ContT (Set r) m), AutoLift c n, Monad m, Ord r) => Proxy c -> [a] -> n a
set :: (Monad m, Ord a) => Handler (Set a) m a (Set a)

module Control.Effects.State
get :: (c ~ (ContT (s -> m r) m), AutoLift c n, Monad m) => Proxy c -> n s
put :: (c ~ (ContT (s -> m r) m), AutoLift c n, Monad m) => Proxy c -> s -> n ()
ref :: Monad m => s -> Handler (s -> m a) m a a

module Control.Effects.Writer
tell :: (c ~ (ContT (w, r) m), AutoLift c n, Monad m, Monoid w) => Proxy c -> w -> n ()
writer :: (Monad m, Monoid w) => Handler (w, a) m a (w, a)