{-# LANGUAGE QuantifiedConstraints, UndecidableInstances, TupleSections #-}

module Control.Monad.Trans.Elevator where

import Control.Monad.Base
import Control.Monad.Error.Class
import Control.Monad.Reader.Class
import Control.Monad.State.Class
import Control.Monad.Trans
import Control.Monad.Trans.Control
import Control.Monad.Writer.Class
import Data.Kind

newtype Elevator
  (t :: (Type -> Type) -> Type -> Type)
  (m :: Type -> Type)
  (a :: Type)
    = Ascend { Elevator t m a -> t m a
descend :: t m a }
  deriving newtype (Functor (Elevator t m)
a -> Elevator t m a
Functor (Elevator t m)
-> (forall a. a -> Elevator t m a)
-> (forall a b.
    Elevator t m (a -> b) -> Elevator t m a -> Elevator t m b)
-> (forall a b c.
    (a -> b -> c)
    -> Elevator t m a -> Elevator t m b -> Elevator t m c)
-> (forall a b. Elevator t m a -> Elevator t m b -> Elevator t m b)
-> (forall a b. Elevator t m a -> Elevator t m b -> Elevator t m a)
-> Applicative (Elevator t m)
Elevator t m a -> Elevator t m b -> Elevator t m b
Elevator t m a -> Elevator t m b -> Elevator t m a
Elevator t m (a -> b) -> Elevator t m a -> Elevator t m b
(a -> b -> c) -> Elevator t m a -> Elevator t m b -> Elevator t m c
forall a. a -> Elevator t m a
forall a b. Elevator t m a -> Elevator t m b -> Elevator t m a
forall a b. Elevator t m a -> Elevator t m b -> Elevator t m b
forall a b.
Elevator t m (a -> b) -> Elevator t m a -> Elevator t m b
forall a b c.
(a -> b -> c) -> Elevator t m a -> Elevator t m b -> Elevator t m c
forall (f :: * -> *).
Functor f
-> (forall a. a -> f a)
-> (forall a b. f (a -> b) -> f a -> f b)
-> (forall a b c. (a -> b -> c) -> f a -> f b -> f c)
-> (forall a b. f a -> f b -> f b)
-> (forall a b. f a -> f b -> f a)
-> Applicative f
forall (t :: (* -> *) -> * -> *) (m :: * -> *).
Applicative (t m) =>
Functor (Elevator t m)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
Applicative (t m) =>
a -> Elevator t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Applicative (t m) =>
Elevator t m a -> Elevator t m b -> Elevator t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Applicative (t m) =>
Elevator t m a -> Elevator t m b -> Elevator t m b
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Applicative (t m) =>
Elevator t m (a -> b) -> Elevator t m a -> Elevator t m b
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b c.
Applicative (t m) =>
(a -> b -> c) -> Elevator t m a -> Elevator t m b -> Elevator t m c
<* :: Elevator t m a -> Elevator t m b -> Elevator t m a
$c<* :: forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Applicative (t m) =>
Elevator t m a -> Elevator t m b -> Elevator t m a
*> :: Elevator t m a -> Elevator t m b -> Elevator t m b
$c*> :: forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Applicative (t m) =>
Elevator t m a -> Elevator t m b -> Elevator t m b
liftA2 :: (a -> b -> c) -> Elevator t m a -> Elevator t m b -> Elevator t m c
$cliftA2 :: forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b c.
Applicative (t m) =>
(a -> b -> c) -> Elevator t m a -> Elevator t m b -> Elevator t m c
<*> :: Elevator t m (a -> b) -> Elevator t m a -> Elevator t m b
$c<*> :: forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Applicative (t m) =>
Elevator t m (a -> b) -> Elevator t m a -> Elevator t m b
pure :: a -> Elevator t m a
$cpure :: forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
Applicative (t m) =>
a -> Elevator t m a
$cp1Applicative :: forall (t :: (* -> *) -> * -> *) (m :: * -> *).
Applicative (t m) =>
Functor (Elevator t m)
Applicative, a -> Elevator t m b -> Elevator t m a
(a -> b) -> Elevator t m a -> Elevator t m b
(forall a b. (a -> b) -> Elevator t m a -> Elevator t m b)
-> (forall a b. a -> Elevator t m b -> Elevator t m a)
-> Functor (Elevator t m)
forall a b. a -> Elevator t m b -> Elevator t m a
forall a b. (a -> b) -> Elevator t m a -> Elevator t m b
forall (f :: * -> *).
(forall a b. (a -> b) -> f a -> f b)
-> (forall a b. a -> f b -> f a) -> Functor f
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Functor (t m) =>
a -> Elevator t m b -> Elevator t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Functor (t m) =>
(a -> b) -> Elevator t m a -> Elevator t m b
<$ :: a -> Elevator t m b -> Elevator t m a
$c<$ :: forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Functor (t m) =>
a -> Elevator t m b -> Elevator t m a
fmap :: (a -> b) -> Elevator t m a -> Elevator t m b
$cfmap :: forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Functor (t m) =>
(a -> b) -> Elevator t m a -> Elevator t m b
Functor, Applicative (Elevator t m)
a -> Elevator t m a
Applicative (Elevator t m)
-> (forall a b.
    Elevator t m a -> (a -> Elevator t m b) -> Elevator t m b)
-> (forall a b. Elevator t m a -> Elevator t m b -> Elevator t m b)
-> (forall a. a -> Elevator t m a)
-> Monad (Elevator t m)
Elevator t m a -> (a -> Elevator t m b) -> Elevator t m b
Elevator t m a -> Elevator t m b -> Elevator t m b
forall a. a -> Elevator t m a
forall a b. Elevator t m a -> Elevator t m b -> Elevator t m b
forall a b.
Elevator t m a -> (a -> Elevator t m b) -> Elevator t m b
forall (m :: * -> *).
Applicative m
-> (forall a b. m a -> (a -> m b) -> m b)
-> (forall a b. m a -> m b -> m b)
-> (forall a. a -> m a)
-> Monad m
forall (t :: (* -> *) -> * -> *) (m :: * -> *).
Monad (t m) =>
Applicative (Elevator t m)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
Monad (t m) =>
a -> Elevator t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Monad (t m) =>
Elevator t m a -> Elevator t m b -> Elevator t m b
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Monad (t m) =>
Elevator t m a -> (a -> Elevator t m b) -> Elevator t m b
return :: a -> Elevator t m a
$creturn :: forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
Monad (t m) =>
a -> Elevator t m a
>> :: Elevator t m a -> Elevator t m b -> Elevator t m b
$c>> :: forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Monad (t m) =>
Elevator t m a -> Elevator t m b -> Elevator t m b
>>= :: Elevator t m a -> (a -> Elevator t m b) -> Elevator t m b
$c>>= :: forall (t :: (* -> *) -> * -> *) (m :: * -> *) a b.
Monad (t m) =>
Elevator t m a -> (a -> Elevator t m b) -> Elevator t m b
$cp1Monad :: forall (t :: (* -> *) -> * -> *) (m :: * -> *).
Monad (t m) =>
Applicative (Elevator t m)
Monad)

instance (Monad (t m), MonadTrans t, MonadBase b m) => MonadBase b (Elevator t m) where
  liftBase :: b α -> Elevator t m α
liftBase = t m α -> Elevator t m α
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m α -> Elevator t m α)
-> (b α -> t m α) -> b α -> Elevator t m α
forall b c a. (b -> c) -> (a -> b) -> a -> c
. m α -> t m α
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift (m α -> t m α) -> (b α -> m α) -> b α -> t m α
forall b c a. (b -> c) -> (a -> b) -> a -> c
. b α -> m α
forall (b :: * -> *) (m :: * -> *) α. MonadBase b m => b α -> m α
liftBase

instance (Monad (t m), MonadTransControl t, MonadBaseControl b m) => MonadBaseControl b (Elevator t m) where
  type StM (Elevator t m) a = StM m (StT t a)
  liftBaseWith :: (RunInBase (Elevator t m) b -> b a) -> Elevator t m a
liftBaseWith RunInBase (Elevator t m) b -> b a
f = t m a -> Elevator t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m a -> Elevator t m a) -> t m a -> Elevator t m a
forall a b. (a -> b) -> a -> b
$ (Run t -> m a) -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTransControl t, Monad m) =>
(Run t -> m a) -> t m a
liftWith ((Run t -> m a) -> t m a) -> (Run t -> m a) -> t m a
forall a b. (a -> b) -> a -> b
$ \ Run t
runT -> (RunInBase m b -> b a) -> m a
forall (b :: * -> *) (m :: * -> *) a.
MonadBaseControl b m =>
(RunInBase m b -> b a) -> m a
liftBaseWith ((RunInBase m b -> b a) -> m a) -> (RunInBase m b -> b a) -> m a
forall a b. (a -> b) -> a -> b
$ \ RunInBase m b
runInBase -> RunInBase (Elevator t m) b -> b a
f (RunInBase (Elevator t m) b -> b a)
-> RunInBase (Elevator t m) b -> b a
forall a b. (a -> b) -> a -> b
$ m (StT t a) -> b (StM m (StT t a))
RunInBase m b
runInBase (m (StT t a) -> b (StM m (StT t a)))
-> (Elevator t m a -> m (StT t a))
-> Elevator t m a
-> b (StM m (StT t a))
forall b c a. (b -> c) -> (a -> b) -> a -> c
. t m a -> m (StT t a)
Run t
runT (t m a -> m (StT t a))
-> (Elevator t m a -> t m a) -> Elevator t m a -> m (StT t a)
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Elevator t m a -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
Elevator t m a -> t m a
descend
  restoreM :: StM (Elevator t m) a -> Elevator t m a
restoreM = t m a -> Elevator t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m a -> Elevator t m a)
-> (StM m (StT t a) -> t m a) -> StM m (StT t a) -> Elevator t m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. m (StT t a) -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTransControl t, Monad m) =>
m (StT t a) -> t m a
restoreT (m (StT t a) -> t m a)
-> (StM m (StT t a) -> m (StT t a)) -> StM m (StT t a) -> t m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. StM m (StT t a) -> m (StT t a)
forall (b :: * -> *) (m :: * -> *) a.
MonadBaseControl b m =>
StM m a -> m a
restoreM

instance (Monad (t m), MonadTrans t, MonadIO m) => MonadIO (Elevator t m) where
  liftIO :: IO a -> Elevator t m a
liftIO = t m a -> Elevator t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m a -> Elevator t m a)
-> (IO a -> t m a) -> IO a -> Elevator t m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. m a -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift (m a -> t m a) -> (IO a -> m a) -> IO a -> t m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. IO a -> m a
forall (m :: * -> *) a. MonadIO m => IO a -> m a
liftIO

instance (Monad (t m), MonadTransControl t, MonadError e m) => MonadError e (Elevator t m) where
  throwError :: e -> Elevator t m a
throwError = t m a -> Elevator t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m a -> Elevator t m a) -> (e -> t m a) -> e -> Elevator t m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. m a -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift (m a -> t m a) -> (e -> m a) -> e -> t m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. e -> m a
forall e (m :: * -> *) a. MonadError e m => e -> m a
throwError
  catchError :: Elevator t m a -> (e -> Elevator t m a) -> Elevator t m a
catchError Elevator t m a
throwing e -> Elevator t m a
catching = t m a -> Elevator t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m a -> Elevator t m a) -> t m a -> Elevator t m a
forall a b. (a -> b) -> a -> b
$ (m (StT t a) -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTransControl t, Monad m) =>
m (StT t a) -> t m a
restoreT (m (StT t a) -> t m a)
-> (StT t a -> m (StT t a)) -> StT t a -> t m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. StT t a -> m (StT t a)
forall (f :: * -> *) a. Applicative f => a -> f a
pure (StT t a -> t m a) -> t m (StT t a) -> t m a
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<<) (t m (StT t a) -> t m a) -> t m (StT t a) -> t m a
forall a b. (a -> b) -> a -> b
$ (Run t -> m (StT t a)) -> t m (StT t a)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTransControl t, Monad m) =>
(Run t -> m a) -> t m a
liftWith ((Run t -> m (StT t a)) -> t m (StT t a))
-> (Run t -> m (StT t a)) -> t m (StT t a)
forall a b. (a -> b) -> a -> b
$ \ Run t
runT ->
    m (StT t a) -> (e -> m (StT t a)) -> m (StT t a)
forall e (m :: * -> *) a.
MonadError e m =>
m a -> (e -> m a) -> m a
catchError (t m a -> m (StT t a)
Run t
runT (t m a -> m (StT t a)) -> t m a -> m (StT t a)
forall a b. (a -> b) -> a -> b
$ Elevator t m a -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
Elevator t m a -> t m a
descend Elevator t m a
throwing) (t m a -> m (StT t a)
Run t
runT (t m a -> m (StT t a)) -> (e -> t m a) -> e -> m (StT t a)
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Elevator t m a -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
Elevator t m a -> t m a
descend (Elevator t m a -> t m a) -> (e -> Elevator t m a) -> e -> t m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. e -> Elevator t m a
catching)

instance (Monad (t m), MonadTransControl t, MonadReader r m) => MonadReader r (Elevator t m) where
  ask :: Elevator t m r
ask = t m r -> Elevator t m r
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m r -> Elevator t m r) -> t m r -> Elevator t m r
forall a b. (a -> b) -> a -> b
$ m r -> t m r
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift m r
forall r (m :: * -> *). MonadReader r m => m r
ask
  local :: (r -> r) -> Elevator t m a -> Elevator t m a
local r -> r
f Elevator t m a
tma = t m a -> Elevator t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m a -> Elevator t m a) -> t m a -> Elevator t m a
forall a b. (a -> b) -> a -> b
$ (m (StT t a) -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTransControl t, Monad m) =>
m (StT t a) -> t m a
restoreT (m (StT t a) -> t m a)
-> (StT t a -> m (StT t a)) -> StT t a -> t m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. StT t a -> m (StT t a)
forall (f :: * -> *) a. Applicative f => a -> f a
pure (StT t a -> t m a) -> t m (StT t a) -> t m a
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<<) (t m (StT t a) -> t m a) -> t m (StT t a) -> t m a
forall a b. (a -> b) -> a -> b
$ (Run t -> m (StT t a)) -> t m (StT t a)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTransControl t, Monad m) =>
(Run t -> m a) -> t m a
liftWith ((Run t -> m (StT t a)) -> t m (StT t a))
-> (Run t -> m (StT t a)) -> t m (StT t a)
forall a b. (a -> b) -> a -> b
$ \ Run t
runT ->
    (r -> r) -> m (StT t a) -> m (StT t a)
forall r (m :: * -> *) a. MonadReader r m => (r -> r) -> m a -> m a
local r -> r
f (m (StT t a) -> m (StT t a)) -> m (StT t a) -> m (StT t a)
forall a b. (a -> b) -> a -> b
$ t m a -> m (StT t a)
Run t
runT (t m a -> m (StT t a)) -> t m a -> m (StT t a)
forall a b. (a -> b) -> a -> b
$ Elevator t m a -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
Elevator t m a -> t m a
descend Elevator t m a
tma

instance (Monad (t m), MonadTrans t, MonadState s m) => MonadState s (Elevator t m) where
  get :: Elevator t m s
get = t m s -> Elevator t m s
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m s -> Elevator t m s) -> t m s -> Elevator t m s
forall a b. (a -> b) -> a -> b
$ m s -> t m s
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift m s
forall s (m :: * -> *). MonadState s m => m s
get
  put :: s -> Elevator t m ()
put = t m () -> Elevator t m ()
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m () -> Elevator t m ())
-> (s -> t m ()) -> s -> Elevator t m ()
forall b c a. (b -> c) -> (a -> b) -> a -> c
. m () -> t m ()
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift (m () -> t m ()) -> (s -> m ()) -> s -> t m ()
forall b c a. (b -> c) -> (a -> b) -> a -> c
. s -> m ()
forall s (m :: * -> *). MonadState s m => s -> m ()
put

instance (Monad (t m), MonadTransControl t, MonadWriter w m) => MonadWriter w (Elevator t m) where
  tell :: w -> Elevator t m ()
tell = t m () -> Elevator t m ()
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m () -> Elevator t m ())
-> (w -> t m ()) -> w -> Elevator t m ()
forall b c a. (b -> c) -> (a -> b) -> a -> c
. m () -> t m ()
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift (m () -> t m ()) -> (w -> m ()) -> w -> t m ()
forall b c a. (b -> c) -> (a -> b) -> a -> c
. w -> m ()
forall w (m :: * -> *). MonadWriter w m => w -> m ()
tell
  listen :: Elevator t m a -> Elevator t m (a, w)
listen Elevator t m a
tma = t m (a, w) -> Elevator t m (a, w)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m (a, w) -> Elevator t m (a, w))
-> t m (a, w) -> Elevator t m (a, w)
forall a b. (a -> b) -> a -> b
$ (Run t -> m (StT t a, w)) -> t m (StT t a, w)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTransControl t, Monad m) =>
(Run t -> m a) -> t m a
liftWith (\ Run t
runT -> m (StT t a) -> m (StT t a, w)
forall w (m :: * -> *) a. MonadWriter w m => m a -> m (a, w)
listen (m (StT t a) -> m (StT t a, w)) -> m (StT t a) -> m (StT t a, w)
forall a b. (a -> b) -> a -> b
$ t m a -> m (StT t a)
Run t
runT (t m a -> m (StT t a)) -> t m a -> m (StT t a)
forall a b. (a -> b) -> a -> b
$ Elevator t m a -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
Elevator t m a -> t m a
descend Elevator t m a
tma) t m (StT t a, w) -> ((StT t a, w) -> t m (a, w)) -> t m (a, w)
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= \ (StT t a
sta, w
w) ->
    (, w
w) (a -> (a, w)) -> t m a -> t m (a, w)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> m (StT t a) -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTransControl t, Monad m) =>
m (StT t a) -> t m a
restoreT (StT t a -> m (StT t a)
forall (f :: * -> *) a. Applicative f => a -> f a
pure StT t a
sta)
  pass :: Elevator t m (a, w -> w) -> Elevator t m a
pass Elevator t m (a, w -> w)
tma = t m a -> Elevator t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
t m a -> Elevator t m a
Ascend (t m a -> Elevator t m a) -> t m a -> Elevator t m a
forall a b. (a -> b) -> a -> b
$ m a -> t m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift (m a -> t m a) -> ((a, w -> w) -> m a) -> (a, w -> w) -> t m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. m (a, w -> w) -> m a
forall w (m :: * -> *) a. MonadWriter w m => m (a, w -> w) -> m a
pass (m (a, w -> w) -> m a)
-> ((a, w -> w) -> m (a, w -> w)) -> (a, w -> w) -> m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. (a, w -> w) -> m (a, w -> w)
forall (f :: * -> *) a. Applicative f => a -> f a
pure ((a, w -> w) -> t m a) -> t m (a, w -> w) -> t m a
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< Elevator t m (a, w -> w) -> t m (a, w -> w)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
Elevator t m a -> t m a
descend Elevator t m (a, w -> w)
tma