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


-- | Extensible objects
--   
@package objective
@version 0.3

module Control.Object

-- | The type 'Object e m' represents objects which can handle messages
--   <tt>e</tt>, perform actions in the environment <tt>m</tt>. It can be
--   thought of as an automaton that converts effects. <a>Object</a>s can
--   be composed just like functions using <a>.&gt;&gt;.</a>; the identity
--   element is <a>echo</a>.
newtype Object e m
Object :: (forall x. e x -> m (x, Object e m)) -> Object e m
runObject :: Object e m -> forall x. e x -> m (x, Object e m)

-- | Lift a natural transformation into an object.
liftO :: Functor f => (forall x. e x -> f x) -> Object e f

-- | Change the workspace of the object.
transObject :: Functor g => (forall x. f x -> g x) -> Object e f -> Object e g

-- | Apply a function to the messages coming into the object.
adaptObject :: Functor m => (forall x. e x -> f x) -> Object f m -> Object e m

-- | Parrots messages given.
echo :: Functor e => Object e e

-- | Compose two objects (aka Dependency Injection).
(.>>.) :: Functor n => Object e m -> Object m n -> Object e n

-- | Build an object.
oneshot :: (Functor e, Monad m) => (forall a. e (m a) -> m a) -> Object e m

-- | Build a stateful object.
stateful :: Monad m => (forall a. e a -> StateT s m a) -> s -> Object e m

-- | Build a stateful object, sharing out the state.
sharing :: Monad m => (forall a. e a -> StateT s m a) -> s -> Object (AccessT s e) m

-- | Like <tt>MonadState</tt>, but doesn't require <a>Monad</a> as a
--   prerequisite.
class Stateful s f | f -> s
get_ :: Stateful s f => f s
put_ :: Stateful s f => s -> f ()

-- | Inflicts external state accessibility to arbitrary effects.
data AccessT s f a
Get :: (s -> a) -> AccessT s f a
Put :: s -> a -> AccessT s f a
LiftAccessT :: (f a) -> AccessT s f a

-- | A mutable variable.
variable :: Applicative f => s -> Object (Access s) f
type Access s = AccessT s Zero

-- | Convert a <i>method sequence</i> into a sequential <i>method
--   execution</i>.
sequential :: Monad m => Object e m -> Object (Free e) m
instance Typeable Object
instance Typeable AccessT
instance Functor f => Functor (AccessT s f)
instance (Functor f, Stateful s f) => Stateful s (Free f)
instance Stateful s (AccessT s f)

module Control.Monad.Objective.Class
class Monad m => MonadObjective m where data family Address (e :: * -> *) (m :: * -> *) type family Residence (m :: * -> *) :: * -> *
(.-) :: MonadObjective m => Address e m -> e a -> m a
new :: MonadObjective m => Object e (Residence m) -> m (Address e m)

-- | Old synonym for <a>new</a>.

-- | <i>Deprecated: Use new instead of misleading invoke</i>
invoke :: MonadObjective m => Object e (Residence m) -> m (Address e m)
(.&) :: (MonadObjective m, Stateful s e) => Address e m -> StateT s m a -> m a

-- | like <a>sequential</a>, but it allows ad-hoc use of <a>Free</a>.
(.|-) :: MonadObjective m => Address e m -> Free e a -> m a
instance (Monoid w, MonadObjective m) => MonadObjective (WriterT w m)
instance (Monoid w, MonadObjective m) => MonadObjective (WriterT w m)
instance MonadObjective m => MonadObjective (StateT s m)
instance MonadObjective m => MonadObjective (StateT s m)
instance MonadObjective m => MonadObjective (MaybeT m)
instance MonadObjective m => MonadObjective (ListT m)
instance MonadObjective m => MonadObjective (IdentityT m)
instance MonadObjective m => MonadObjective (ExceptT er m)
instance MonadObjective m => MonadObjective (ContT r m)
instance (Monoid w, MonadObjective m) => MonadObjective (RWST r w s m)
instance (Monoid w, MonadObjective m) => MonadObjective (RWST r w s m)
instance MonadObjective m => MonadObjective (ReaderT r m)


-- | <a>MonadObjective</a> <a>IO</a> using MVar
module Control.Monad.Objective.IO
instance MonadObjective IO

module Control.Monad.Objective