{-# LANGUAGE CPP #-}
#if __GLASGOW_HASKELL__ >= 702
{-# LANGUAGE Safe #-}
#endif
#if __GLASGOW_HASKELL__ >= 710
{-# LANGUAGE AutoDeriveTypeable #-}
#endif
module Control.Monad.Trans.Except (
Except,
except,
runExcept,
mapExcept,
withExcept,
ExceptT(ExceptT),
runExceptT,
mapExceptT,
withExceptT,
throwE,
catchE,
liftCallCC,
liftListen,
liftPass,
) where
import Control.Monad.IO.Class
import Control.Monad.Signatures
import Control.Monad.Trans.Class
import Data.Functor.Classes
#if MIN_VERSION_base(4,12,0)
import Data.Functor.Contravariant
#endif
import Data.Functor.Identity
import Control.Applicative
import Control.Monad
#if MIN_VERSION_base(4,9,0)
import qualified Control.Monad.Fail as Fail
#endif
import Control.Monad.Fix
#if MIN_VERSION_base(4,4,0)
import Control.Monad.Zip (MonadZip(mzipWith))
#endif
import Data.Foldable (Foldable(foldMap))
import Data.Monoid
import Data.Traversable (Traversable(traverse))
type Except e = ExceptT e Identity
except :: (Monad m) => Either e a -> ExceptT e m a
except :: forall (m :: * -> *) e a. Monad m => Either e a -> ExceptT e m a
except Either e a
m = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT (forall (m :: * -> *) a. Monad m => a -> m a
return Either e a
m)
{-# INLINE except #-}
runExcept :: Except e a -> Either e a
runExcept :: forall e a. Except e a -> Either e a
runExcept (ExceptT Identity (Either e a)
m) = forall a. Identity a -> a
runIdentity Identity (Either e a)
m
{-# INLINE runExcept #-}
mapExcept :: (Either e a -> Either e' b)
-> Except e a
-> Except e' b
mapExcept :: forall e a e' b.
(Either e a -> Either e' b) -> Except e a -> Except e' b
mapExcept Either e a -> Either e' b
f = forall (m :: * -> *) e a (n :: * -> *) e' b.
(m (Either e a) -> n (Either e' b))
-> ExceptT e m a -> ExceptT e' n b
mapExceptT (forall a. a -> Identity a
Identity forall b c a. (b -> c) -> (a -> b) -> a -> c
. Either e a -> Either e' b
f forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a. Identity a -> a
runIdentity)
{-# INLINE mapExcept #-}
withExcept :: (e -> e') -> Except e a -> Except e' a
withExcept :: forall e e' a. (e -> e') -> Except e a -> Except e' a
withExcept = forall (m :: * -> *) e e' a.
Functor m =>
(e -> e') -> ExceptT e m a -> ExceptT e' m a
withExceptT
{-# INLINE withExcept #-}
newtype ExceptT e m a = ExceptT (m (Either e a))
instance (Eq e, Eq1 m) => Eq1 (ExceptT e m) where
liftEq :: forall a b.
(a -> b -> Bool) -> ExceptT e m a -> ExceptT e m b -> Bool
liftEq a -> b -> Bool
eq (ExceptT m (Either e a)
x) (ExceptT m (Either e b)
y) = forall (f :: * -> *) a b.
Eq1 f =>
(a -> b -> Bool) -> f a -> f b -> Bool
liftEq (forall (f :: * -> *) a b.
Eq1 f =>
(a -> b -> Bool) -> f a -> f b -> Bool
liftEq a -> b -> Bool
eq) m (Either e a)
x m (Either e b)
y
{-# INLINE liftEq #-}
instance (Ord e, Ord1 m) => Ord1 (ExceptT e m) where
liftCompare :: forall a b.
(a -> b -> Ordering) -> ExceptT e m a -> ExceptT e m b -> Ordering
liftCompare a -> b -> Ordering
comp (ExceptT m (Either e a)
x) (ExceptT m (Either e b)
y) =
forall (f :: * -> *) a b.
Ord1 f =>
(a -> b -> Ordering) -> f a -> f b -> Ordering
liftCompare (forall (f :: * -> *) a b.
Ord1 f =>
(a -> b -> Ordering) -> f a -> f b -> Ordering
liftCompare a -> b -> Ordering
comp) m (Either e a)
x m (Either e b)
y
{-# INLINE liftCompare #-}
instance (Read e, Read1 m) => Read1 (ExceptT e m) where
liftReadsPrec :: forall a.
(Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (ExceptT e m a)
liftReadsPrec Int -> ReadS a
rp ReadS [a]
rl = forall a. (String -> ReadS a) -> Int -> ReadS a
readsData forall a b. (a -> b) -> a -> b
$
forall a t.
(Int -> ReadS a) -> String -> (a -> t) -> String -> ReadS t
readsUnaryWith (forall (f :: * -> *) a.
Read1 f =>
(Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (f a)
liftReadsPrec Int -> ReadS (Either e a)
rp' ReadS [Either e a]
rl') String
"ExceptT" forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT
where
rp' :: Int -> ReadS (Either e a)
rp' = forall (f :: * -> *) a.
Read1 f =>
(Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (f a)
liftReadsPrec Int -> ReadS a
rp ReadS [a]
rl
rl' :: ReadS [Either e a]
rl' = forall (f :: * -> *) a.
Read1 f =>
(Int -> ReadS a) -> ReadS [a] -> ReadS [f a]
liftReadList Int -> ReadS a
rp ReadS [a]
rl
instance (Show e, Show1 m) => Show1 (ExceptT e m) where
liftShowsPrec :: forall a.
(Int -> a -> ShowS)
-> ([a] -> ShowS) -> Int -> ExceptT e m a -> ShowS
liftShowsPrec Int -> a -> ShowS
sp [a] -> ShowS
sl Int
d (ExceptT m (Either e a)
m) =
forall a. (Int -> a -> ShowS) -> String -> Int -> a -> ShowS
showsUnaryWith (forall (f :: * -> *) a.
Show1 f =>
(Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> f a -> ShowS
liftShowsPrec Int -> Either e a -> ShowS
sp' [Either e a] -> ShowS
sl') String
"ExceptT" Int
d m (Either e a)
m
where
sp' :: Int -> Either e a -> ShowS
sp' = forall (f :: * -> *) a.
Show1 f =>
(Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> f a -> ShowS
liftShowsPrec Int -> a -> ShowS
sp [a] -> ShowS
sl
sl' :: [Either e a] -> ShowS
sl' = forall (f :: * -> *) a.
Show1 f =>
(Int -> a -> ShowS) -> ([a] -> ShowS) -> [f a] -> ShowS
liftShowList Int -> a -> ShowS
sp [a] -> ShowS
sl
instance (Eq e, Eq1 m, Eq a) => Eq (ExceptT e m a)
where == :: ExceptT e m a -> ExceptT e m a -> Bool
(==) = forall (f :: * -> *) a. (Eq1 f, Eq a) => f a -> f a -> Bool
eq1
instance (Ord e, Ord1 m, Ord a) => Ord (ExceptT e m a)
where compare :: ExceptT e m a -> ExceptT e m a -> Ordering
compare = forall (f :: * -> *) a. (Ord1 f, Ord a) => f a -> f a -> Ordering
compare1
instance (Read e, Read1 m, Read a) => Read (ExceptT e m a) where
readsPrec :: Int -> ReadS (ExceptT e m a)
readsPrec = forall (f :: * -> *) a. (Read1 f, Read a) => Int -> ReadS (f a)
readsPrec1
instance (Show e, Show1 m, Show a) => Show (ExceptT e m a) where
showsPrec :: Int -> ExceptT e m a -> ShowS
showsPrec = forall (f :: * -> *) a. (Show1 f, Show a) => Int -> f a -> ShowS
showsPrec1
runExceptT :: ExceptT e m a -> m (Either e a)
runExceptT :: forall e (m :: * -> *) a. ExceptT e m a -> m (Either e a)
runExceptT (ExceptT m (Either e a)
m) = m (Either e a)
m
{-# INLINE runExceptT #-}
mapExceptT :: (m (Either e a) -> n (Either e' b))
-> ExceptT e m a
-> ExceptT e' n b
mapExceptT :: forall (m :: * -> *) e a (n :: * -> *) e' b.
(m (Either e a) -> n (Either e' b))
-> ExceptT e m a -> ExceptT e' n b
mapExceptT m (Either e a) -> n (Either e' b)
f ExceptT e m a
m = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall a b. (a -> b) -> a -> b
$ m (Either e a) -> n (Either e' b)
f (forall e (m :: * -> *) a. ExceptT e m a -> m (Either e a)
runExceptT ExceptT e m a
m)
{-# INLINE mapExceptT #-}
withExceptT :: (Functor m) => (e -> e') -> ExceptT e m a -> ExceptT e' m a
withExceptT :: forall (m :: * -> *) e e' a.
Functor m =>
(e -> e') -> ExceptT e m a -> ExceptT e' m a
withExceptT e -> e'
f = forall (m :: * -> *) e a (n :: * -> *) e' b.
(m (Either e a) -> n (Either e' b))
-> ExceptT e m a -> ExceptT e' n b
mapExceptT forall a b. (a -> b) -> a -> b
$ forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap forall a b. (a -> b) -> a -> b
$ forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall a b. a -> Either a b
Left forall b c a. (b -> c) -> (a -> b) -> a -> c
. e -> e'
f) forall a b. b -> Either a b
Right
{-# INLINE withExceptT #-}
instance (Functor m) => Functor (ExceptT e m) where
fmap :: forall a b. (a -> b) -> ExceptT e m a -> ExceptT e m b
fmap a -> b
f = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap (forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap a -> b
f) forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall e (m :: * -> *) a. ExceptT e m a -> m (Either e a)
runExceptT
{-# INLINE fmap #-}
instance (Foldable f) => Foldable (ExceptT e f) where
foldMap :: forall m a. Monoid m => (a -> m) -> ExceptT e f a -> m
foldMap a -> m
f (ExceptT f (Either e a)
a) = forall (t :: * -> *) m a.
(Foldable t, Monoid m) =>
(a -> m) -> t a -> m
foldMap (forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall a b. a -> b -> a
const forall a. Monoid a => a
mempty) a -> m
f) f (Either e a)
a
{-# INLINE foldMap #-}
instance (Traversable f) => Traversable (ExceptT e f) where
traverse :: forall (f :: * -> *) a b.
Applicative f =>
(a -> f b) -> ExceptT e f a -> f (ExceptT e f b)
traverse a -> f b
f (ExceptT f (Either e a)
a) =
forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> forall (t :: * -> *) (f :: * -> *) a b.
(Traversable t, Applicative f) =>
(a -> f b) -> t a -> f (t b)
traverse (forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall (f :: * -> *) a. Applicative f => a -> f a
pure forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left) (forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap forall a b. b -> Either a b
Right forall b c a. (b -> c) -> (a -> b) -> a -> c
. a -> f b
f)) f (Either e a)
a
{-# INLINE traverse #-}
instance (Functor m, Monad m) => Applicative (ExceptT e m) where
pure :: forall a. a -> ExceptT e m a
pure a
a = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a. Monad m => a -> m a
return (forall a b. b -> Either a b
Right a
a)
{-# INLINE pure #-}
ExceptT m (Either e (a -> b))
f <*> :: forall a b. ExceptT e m (a -> b) -> ExceptT e m a -> ExceptT e m b
<*> ExceptT m (Either e a)
v = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall a b. (a -> b) -> a -> b
$ do
Either e (a -> b)
mf <- m (Either e (a -> b))
f
case Either e (a -> b)
mf of
Left e
e -> forall (m :: * -> *) a. Monad m => a -> m a
return (forall a b. a -> Either a b
Left e
e)
Right a -> b
k -> do
Either e a
mv <- m (Either e a)
v
case Either e a
mv of
Left e
e -> forall (m :: * -> *) a. Monad m => a -> m a
return (forall a b. a -> Either a b
Left e
e)
Right a
x -> forall (m :: * -> *) a. Monad m => a -> m a
return (forall a b. b -> Either a b
Right (a -> b
k a
x))
{-# INLINEABLE (<*>) #-}
ExceptT e m a
m *> :: forall a b. ExceptT e m a -> ExceptT e m b -> ExceptT e m b
*> ExceptT e m b
k = ExceptT e m a
m forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= \a
_ -> ExceptT e m b
k
{-# INLINE (*>) #-}
instance (Functor m, Monad m, Monoid e) => Alternative (ExceptT e m) where
empty :: forall a. ExceptT e m a
empty = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a. Monad m => a -> m a
return (forall a b. a -> Either a b
Left forall a. Monoid a => a
mempty)
{-# INLINE empty #-}
ExceptT m (Either e a)
mx <|> :: forall a. ExceptT e m a -> ExceptT e m a -> ExceptT e m a
<|> ExceptT m (Either e a)
my = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall a b. (a -> b) -> a -> b
$ do
Either e a
ex <- m (Either e a)
mx
case Either e a
ex of
Left e
e -> forall (m :: * -> *) a1 r. Monad m => (a1 -> r) -> m a1 -> m r
liftM (forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall a b. a -> Either a b
Left forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a. Monoid a => a -> a -> a
mappend e
e) forall a b. b -> Either a b
Right) m (Either e a)
my
Right a
x -> forall (m :: * -> *) a. Monad m => a -> m a
return (forall a b. b -> Either a b
Right a
x)
{-# INLINEABLE (<|>) #-}
instance (Monad m) => Monad (ExceptT e m) where
#if !(MIN_VERSION_base(4,8,0))
return a = ExceptT $ return (Right a)
{-# INLINE return #-}
#endif
ExceptT e m a
m >>= :: forall a b. ExceptT e m a -> (a -> ExceptT e m b) -> ExceptT e m b
>>= a -> ExceptT e m b
k = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall a b. (a -> b) -> a -> b
$ do
Either e a
a <- forall e (m :: * -> *) a. ExceptT e m a -> m (Either e a)
runExceptT ExceptT e m a
m
case Either e a
a of
Left e
e -> forall (m :: * -> *) a. Monad m => a -> m a
return (forall a b. a -> Either a b
Left e
e)
Right a
x -> forall e (m :: * -> *) a. ExceptT e m a -> m (Either e a)
runExceptT (a -> ExceptT e m b
k a
x)
{-# INLINE (>>=) #-}
#if !(MIN_VERSION_base(4,13,0))
fail = ExceptT . fail
{-# INLINE fail #-}
#endif
#if MIN_VERSION_base(4,9,0)
instance (Fail.MonadFail m) => Fail.MonadFail (ExceptT e m) where
fail :: forall a. String -> ExceptT e m a
fail = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a. MonadFail m => String -> m a
Fail.fail
{-# INLINE fail #-}
#endif
instance (Monad m, Monoid e) => MonadPlus (ExceptT e m) where
mzero :: forall a. ExceptT e m a
mzero = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a. Monad m => a -> m a
return (forall a b. a -> Either a b
Left forall a. Monoid a => a
mempty)
{-# INLINE mzero #-}
ExceptT m (Either e a)
mx mplus :: forall a. ExceptT e m a -> ExceptT e m a -> ExceptT e m a
`mplus` ExceptT m (Either e a)
my = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall a b. (a -> b) -> a -> b
$ do
Either e a
ex <- m (Either e a)
mx
case Either e a
ex of
Left e
e -> forall (m :: * -> *) a1 r. Monad m => (a1 -> r) -> m a1 -> m r
liftM (forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall a b. a -> Either a b
Left forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a. Monoid a => a -> a -> a
mappend e
e) forall a b. b -> Either a b
Right) m (Either e a)
my
Right a
x -> forall (m :: * -> *) a. Monad m => a -> m a
return (forall a b. b -> Either a b
Right a
x)
{-# INLINEABLE mplus #-}
instance (MonadFix m) => MonadFix (ExceptT e m) where
mfix :: forall a. (a -> ExceptT e m a) -> ExceptT e m a
mfix a -> ExceptT e m a
f = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT (forall (m :: * -> *) a. MonadFix m => (a -> m a) -> m a
mfix (forall e (m :: * -> *) a. ExceptT e m a -> m (Either e a)
runExceptT forall b c a. (b -> c) -> (a -> b) -> a -> c
. a -> ExceptT e m a
f forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall a b. a -> b -> a
const forall {a}. a
bomb) forall a. a -> a
id))
where bomb :: a
bomb = forall a. HasCallStack => String -> a
error String
"mfix (ExceptT): inner computation returned Left value"
{-# INLINE mfix #-}
instance MonadTrans (ExceptT e) where
lift :: forall (m :: * -> *) a. Monad m => m a -> ExceptT e m a
lift = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a1 r. Monad m => (a1 -> r) -> m a1 -> m r
liftM forall a b. b -> Either a b
Right
{-# INLINE lift #-}
instance (MonadIO m) => MonadIO (ExceptT e m) where
liftIO :: forall a. IO a -> ExceptT e m a
liftIO = forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a. MonadIO m => IO a -> m a
liftIO
{-# INLINE liftIO #-}
#if MIN_VERSION_base(4,4,0)
instance (MonadZip m) => MonadZip (ExceptT e m) where
mzipWith :: forall a b c.
(a -> b -> c) -> ExceptT e m a -> ExceptT e m b -> ExceptT e m c
mzipWith a -> b -> c
f (ExceptT m (Either e a)
a) (ExceptT m (Either e b)
b) = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a b c.
MonadZip m =>
(a -> b -> c) -> m a -> m b -> m c
mzipWith (forall (f :: * -> *) a b c.
Applicative f =>
(a -> b -> c) -> f a -> f b -> f c
liftA2 a -> b -> c
f) m (Either e a)
a m (Either e b)
b
{-# INLINE mzipWith #-}
#endif
#if MIN_VERSION_base(4,12,0)
instance Contravariant m => Contravariant (ExceptT e m) where
contramap :: forall a' a. (a' -> a) -> ExceptT e m a -> ExceptT e m a'
contramap a' -> a
f = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (f :: * -> *) a' a.
Contravariant f =>
(a' -> a) -> f a -> f a'
contramap (forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap a' -> a
f) forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall e (m :: * -> *) a. ExceptT e m a -> m (Either e a)
runExceptT
{-# INLINE contramap #-}
#endif
throwE :: (Monad m) => e -> ExceptT e m a
throwE :: forall (m :: * -> *) e a. Monad m => e -> ExceptT e m a
throwE = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a. Monad m => a -> m a
return forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left
{-# INLINE throwE #-}
catchE :: (Monad m) =>
ExceptT e m a
-> (e -> ExceptT e' m a)
-> ExceptT e' m a
ExceptT e m a
m catchE :: forall (m :: * -> *) e a e'.
Monad m =>
ExceptT e m a -> (e -> ExceptT e' m a) -> ExceptT e' m a
`catchE` e -> ExceptT e' m a
h = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall a b. (a -> b) -> a -> b
$ do
Either e a
a <- forall e (m :: * -> *) a. ExceptT e m a -> m (Either e a)
runExceptT ExceptT e m a
m
case Either e a
a of
Left e
l -> forall e (m :: * -> *) a. ExceptT e m a -> m (Either e a)
runExceptT (e -> ExceptT e' m a
h e
l)
Right a
r -> forall (m :: * -> *) a. Monad m => a -> m a
return (forall a b. b -> Either a b
Right a
r)
{-# INLINE catchE #-}
liftCallCC :: CallCC m (Either e a) (Either e b) -> CallCC (ExceptT e m) a b
liftCallCC :: forall (m :: * -> *) e a b.
CallCC m (Either e a) (Either e b) -> CallCC (ExceptT e m) a b
liftCallCC CallCC m (Either e a) (Either e b)
callCC (a -> ExceptT e m b) -> ExceptT e m a
f = forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall a b. (a -> b) -> a -> b
$
CallCC m (Either e a) (Either e b)
callCC forall a b. (a -> b) -> a -> b
$ \ Either e a -> m (Either e b)
c ->
forall e (m :: * -> *) a. ExceptT e m a -> m (Either e a)
runExceptT ((a -> ExceptT e m b) -> ExceptT e m a
f (\ a
a -> forall e (m :: * -> *) a. m (Either e a) -> ExceptT e m a
ExceptT forall a b. (a -> b) -> a -> b
$ Either e a -> m (Either e b)
c (forall a b. b -> Either a b
Right a
a)))
{-# INLINE liftCallCC #-}
liftListen :: (Monad m) => Listen w m (Either e a) -> Listen w (ExceptT e m) a
liftListen :: forall (m :: * -> *) w e a.
Monad m =>
Listen w m (Either e a) -> Listen w (ExceptT e m) a
liftListen Listen w m (Either e a)
listen = forall (m :: * -> *) e a (n :: * -> *) e' b.
(m (Either e a) -> n (Either e' b))
-> ExceptT e m a -> ExceptT e' n b
mapExceptT forall a b. (a -> b) -> a -> b
$ \ m (Either e a)
m -> do
(Either e a
a, w
w) <- Listen w m (Either e a)
listen m (Either e a)
m
forall (m :: * -> *) a. Monad m => a -> m a
return forall a b. (a -> b) -> a -> b
$! forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap (\ a
r -> (a
r, w
w)) Either e a
a
{-# INLINE liftListen #-}
liftPass :: (Monad m) => Pass w m (Either e a) -> Pass w (ExceptT e m) a
liftPass :: forall (m :: * -> *) w e a.
Monad m =>
Pass w m (Either e a) -> Pass w (ExceptT e m) a
liftPass Pass w m (Either e a)
pass = forall (m :: * -> *) e a (n :: * -> *) e' b.
(m (Either e a) -> n (Either e' b))
-> ExceptT e m a -> ExceptT e' n b
mapExceptT forall a b. (a -> b) -> a -> b
$ \ m (Either e (a, w -> w))
m -> Pass w m (Either e a)
pass forall a b. (a -> b) -> a -> b
$ do
Either e (a, w -> w)
a <- m (Either e (a, w -> w))
m
forall (m :: * -> *) a. Monad m => a -> m a
return forall a b. (a -> b) -> a -> b
$! case Either e (a, w -> w)
a of
Left e
l -> (forall a b. a -> Either a b
Left e
l, forall a. a -> a
id)
Right (a
r, w -> w
f) -> (forall a b. b -> Either a b
Right a
r, w -> w
f)
{-# INLINE liftPass #-}