{-# LANGUAGE CPP #-}
{-# LANGUAGE ExistentialQuantification #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE UndecidableInstances #-}
#if defined(__GLASGOW_HASKELL__) && __GLASGOW_HASKELL__ >= 702
{-# LANGUAGE Trustworthy #-}
#endif
#ifndef MIN_VERSION_transformers
#define MIN_VERSION_transformers(x,y,z) 1
#endif
#ifndef MIN_VERSION_mtl
#define MIN_VERSION_mtl(x,y,z) 1
#endif
module Control.Monad.Catch.Pure (
CatchT(..), Catch
, runCatch
, mapCatchT
, module Control.Monad.Catch
) where
#if defined(__GLASGOW_HASKELL__) && (__GLASGOW_HASKELL__ >= 706)
import Prelude hiding (foldr)
#else
import Prelude hiding (catch, foldr)
#endif
import Control.Applicative
import Control.Monad.Catch
import qualified Control.Monad.Fail as Fail
import Control.Monad.Reader as Reader
import Control.Monad.RWS
#if __GLASGOW_HASKELL__ < 710
import Data.Foldable
#endif
import Data.Functor.Identity
import Data.Traversable as Traversable
newtype CatchT m a = CatchT { forall (m :: * -> *) a. CatchT m a -> m (Either SomeException a)
runCatchT :: m (Either SomeException a) }
type Catch = CatchT Identity
runCatch :: Catch a -> Either SomeException a
runCatch :: forall a. Catch a -> Either SomeException a
runCatch = Identity (Either SomeException a) -> Either SomeException a
forall a. Identity a -> a
runIdentity (Identity (Either SomeException a) -> Either SomeException a)
-> (Catch a -> Identity (Either SomeException a))
-> Catch a
-> Either SomeException a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Catch a -> Identity (Either SomeException a)
forall (m :: * -> *) a. CatchT m a -> m (Either SomeException a)
runCatchT
instance Monad m => Functor (CatchT m) where
fmap :: forall a b. (a -> b) -> CatchT m a -> CatchT m b
fmap a -> b
f (CatchT m (Either SomeException a)
m) = m (Either SomeException b) -> CatchT m b
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT ((Either SomeException a -> Either SomeException b)
-> m (Either SomeException a) -> m (Either SomeException b)
forall (m :: * -> *) a1 r. Monad m => (a1 -> r) -> m a1 -> m r
liftM ((a -> b) -> Either SomeException a -> Either SomeException b
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap a -> b
f) m (Either SomeException a)
m)
instance Monad m => Applicative (CatchT m) where
pure :: forall a. a -> CatchT m a
pure a
a = m (Either SomeException a) -> CatchT m a
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (Either SomeException a -> m (Either SomeException a)
forall (m :: * -> *) a. Monad m => a -> m a
return (a -> Either SomeException a
forall a b. b -> Either a b
Right a
a))
<*> :: forall a b. CatchT m (a -> b) -> CatchT m a -> CatchT m b
(<*>) = CatchT m (a -> b) -> CatchT m a -> CatchT m b
forall (m :: * -> *) a b. Monad m => m (a -> b) -> m a -> m b
ap
instance Monad m => Monad (CatchT m) where
return :: forall a. a -> CatchT m a
return = a -> CatchT m a
forall (f :: * -> *) a. Applicative f => a -> f a
pure
CatchT m (Either SomeException a)
m >>= :: forall a b. CatchT m a -> (a -> CatchT m b) -> CatchT m b
>>= a -> CatchT m b
k = m (Either SomeException b) -> CatchT m b
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (m (Either SomeException b) -> CatchT m b)
-> m (Either SomeException b) -> CatchT m b
forall a b. (a -> b) -> a -> b
$ m (Either SomeException a)
m m (Either SomeException a)
-> (Either SomeException a -> m (Either SomeException b))
-> m (Either SomeException b)
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= \Either SomeException a
ea -> case Either SomeException a
ea of
Left SomeException
e -> Either SomeException b -> m (Either SomeException b)
forall (m :: * -> *) a. Monad m => a -> m a
return (SomeException -> Either SomeException b
forall a b. a -> Either a b
Left SomeException
e)
Right a
a -> CatchT m b -> m (Either SomeException b)
forall (m :: * -> *) a. CatchT m a -> m (Either SomeException a)
runCatchT (a -> CatchT m b
k a
a)
#if !(MIN_VERSION_base(4,13,0))
fail = Fail.fail
#endif
instance Monad m => Fail.MonadFail (CatchT m) where
fail :: forall a. String -> CatchT m a
fail = m (Either SomeException a) -> CatchT m a
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (m (Either SomeException a) -> CatchT m a)
-> (String -> m (Either SomeException a)) -> String -> CatchT m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Either SomeException a -> m (Either SomeException a)
forall (m :: * -> *) a. Monad m => a -> m a
return (Either SomeException a -> m (Either SomeException a))
-> (String -> Either SomeException a)
-> String
-> m (Either SomeException a)
forall b c a. (b -> c) -> (a -> b) -> a -> c
. SomeException -> Either SomeException a
forall a b. a -> Either a b
Left (SomeException -> Either SomeException a)
-> (String -> SomeException) -> String -> Either SomeException a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. IOError -> SomeException
forall e. Exception e => e -> SomeException
toException (IOError -> SomeException)
-> (String -> IOError) -> String -> SomeException
forall b c a. (b -> c) -> (a -> b) -> a -> c
. String -> IOError
userError
instance MonadFix m => MonadFix (CatchT m) where
mfix :: forall a. (a -> CatchT m a) -> CatchT m a
mfix a -> CatchT m a
f = m (Either SomeException a) -> CatchT m a
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (m (Either SomeException a) -> CatchT m a)
-> m (Either SomeException a) -> CatchT m a
forall a b. (a -> b) -> a -> b
$ (Either SomeException a -> m (Either SomeException a))
-> m (Either SomeException a)
forall (m :: * -> *) a. MonadFix m => (a -> m a) -> m a
mfix ((Either SomeException a -> m (Either SomeException a))
-> m (Either SomeException a))
-> (Either SomeException a -> m (Either SomeException a))
-> m (Either SomeException a)
forall a b. (a -> b) -> a -> b
$ \Either SomeException a
a -> CatchT m a -> m (Either SomeException a)
forall (m :: * -> *) a. CatchT m a -> m (Either SomeException a)
runCatchT (CatchT m a -> m (Either SomeException a))
-> CatchT m a -> m (Either SomeException a)
forall a b. (a -> b) -> a -> b
$ a -> CatchT m a
f (a -> CatchT m a) -> a -> CatchT m a
forall a b. (a -> b) -> a -> b
$ case Either SomeException a
a of
Right a
r -> a
r
Either SomeException a
_ -> String -> a
forall a. HasCallStack => String -> a
error String
"empty mfix argument"
instance Foldable m => Foldable (CatchT m) where
foldMap :: forall m a. Monoid m => (a -> m) -> CatchT m a -> m
foldMap a -> m
f (CatchT m (Either SomeException a)
m) = (Either SomeException a -> m) -> m (Either SomeException a) -> m
forall (t :: * -> *) m a.
(Foldable t, Monoid m) =>
(a -> m) -> t a -> m
foldMap ((a -> m) -> Either SomeException a -> m
forall {t} {t} {a}. Monoid t => (t -> t) -> Either a t -> t
foldMapEither a -> m
f) m (Either SomeException a)
m where
foldMapEither :: (t -> t) -> Either a t -> t
foldMapEither t -> t
g (Right t
a) = t -> t
g t
a
foldMapEither t -> t
_ (Left a
_) = t
forall a. Monoid a => a
mempty
instance (Monad m, Traversable m) => Traversable (CatchT m) where
traverse :: forall (f :: * -> *) a b.
Applicative f =>
(a -> f b) -> CatchT m a -> f (CatchT m b)
traverse a -> f b
f (CatchT m (Either SomeException a)
m) = m (Either SomeException b) -> CatchT m b
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (m (Either SomeException b) -> CatchT m b)
-> f (m (Either SomeException b)) -> f (CatchT m b)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> (Either SomeException a -> f (Either SomeException b))
-> m (Either SomeException a) -> f (m (Either SomeException b))
forall (t :: * -> *) (f :: * -> *) a b.
(Traversable t, Applicative f) =>
(a -> f b) -> t a -> f (t b)
Traversable.traverse ((a -> f b) -> Either SomeException a -> f (Either SomeException b)
forall {f :: * -> *} {t} {a} {a}.
Applicative f =>
(t -> f a) -> Either a t -> f (Either a a)
traverseEither a -> f b
f) m (Either SomeException a)
m where
traverseEither :: (t -> f a) -> Either a t -> f (Either a a)
traverseEither t -> f a
g (Right t
a) = a -> Either a a
forall a b. b -> Either a b
Right (a -> Either a a) -> f a -> f (Either a a)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> t -> f a
g t
a
traverseEither t -> f a
_ (Left a
e) = Either a a -> f (Either a a)
forall (f :: * -> *) a. Applicative f => a -> f a
pure (a -> Either a a
forall a b. a -> Either a b
Left a
e)
instance Monad m => Alternative (CatchT m) where
empty :: forall a. CatchT m a
empty = CatchT m a
forall (m :: * -> *) a. MonadPlus m => m a
mzero
<|> :: forall a. CatchT m a -> CatchT m a -> CatchT m a
(<|>) = CatchT m a -> CatchT m a -> CatchT m a
forall (m :: * -> *) a. MonadPlus m => m a -> m a -> m a
mplus
instance Monad m => MonadPlus (CatchT m) where
mzero :: forall a. CatchT m a
mzero = m (Either SomeException a) -> CatchT m a
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (m (Either SomeException a) -> CatchT m a)
-> m (Either SomeException a) -> CatchT m a
forall a b. (a -> b) -> a -> b
$ Either SomeException a -> m (Either SomeException a)
forall (m :: * -> *) a. Monad m => a -> m a
return (Either SomeException a -> m (Either SomeException a))
-> Either SomeException a -> m (Either SomeException a)
forall a b. (a -> b) -> a -> b
$ SomeException -> Either SomeException a
forall a b. a -> Either a b
Left (SomeException -> Either SomeException a)
-> SomeException -> Either SomeException a
forall a b. (a -> b) -> a -> b
$ IOError -> SomeException
forall e. Exception e => e -> SomeException
toException (IOError -> SomeException) -> IOError -> SomeException
forall a b. (a -> b) -> a -> b
$ String -> IOError
userError String
""
mplus :: forall a. CatchT m a -> CatchT m a -> CatchT m a
mplus (CatchT m (Either SomeException a)
m) (CatchT m (Either SomeException a)
n) = m (Either SomeException a) -> CatchT m a
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (m (Either SomeException a) -> CatchT m a)
-> m (Either SomeException a) -> CatchT m a
forall a b. (a -> b) -> a -> b
$ m (Either SomeException a)
m m (Either SomeException a)
-> (Either SomeException a -> m (Either SomeException a))
-> m (Either SomeException a)
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= \Either SomeException a
ea -> case Either SomeException a
ea of
Left SomeException
_ -> m (Either SomeException a)
n
Right a
a -> Either SomeException a -> m (Either SomeException a)
forall (m :: * -> *) a. Monad m => a -> m a
return (a -> Either SomeException a
forall a b. b -> Either a b
Right a
a)
instance MonadTrans CatchT where
lift :: forall (m :: * -> *) a. Monad m => m a -> CatchT m a
lift m a
m = m (Either SomeException a) -> CatchT m a
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (m (Either SomeException a) -> CatchT m a)
-> m (Either SomeException a) -> CatchT m a
forall a b. (a -> b) -> a -> b
$ do
a
a <- m a
m
Either SomeException a -> m (Either SomeException a)
forall (m :: * -> *) a. Monad m => a -> m a
return (Either SomeException a -> m (Either SomeException a))
-> Either SomeException a -> m (Either SomeException a)
forall a b. (a -> b) -> a -> b
$ a -> Either SomeException a
forall a b. b -> Either a b
Right a
a
instance MonadIO m => MonadIO (CatchT m) where
liftIO :: forall a. IO a -> CatchT m a
liftIO IO a
m = m (Either SomeException a) -> CatchT m a
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (m (Either SomeException a) -> CatchT m a)
-> m (Either SomeException a) -> CatchT m a
forall a b. (a -> b) -> a -> b
$ do
a
a <- IO a -> m a
forall (m :: * -> *) a. MonadIO m => IO a -> m a
liftIO IO a
m
Either SomeException a -> m (Either SomeException a)
forall (m :: * -> *) a. Monad m => a -> m a
return (Either SomeException a -> m (Either SomeException a))
-> Either SomeException a -> m (Either SomeException a)
forall a b. (a -> b) -> a -> b
$ a -> Either SomeException a
forall a b. b -> Either a b
Right a
a
instance Monad m => MonadThrow (CatchT m) where
throwM :: forall e a. Exception e => e -> CatchT m a
throwM = m (Either SomeException a) -> CatchT m a
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (m (Either SomeException a) -> CatchT m a)
-> (e -> m (Either SomeException a)) -> e -> CatchT m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Either SomeException a -> m (Either SomeException a)
forall (m :: * -> *) a. Monad m => a -> m a
return (Either SomeException a -> m (Either SomeException a))
-> (e -> Either SomeException a) -> e -> m (Either SomeException a)
forall b c a. (b -> c) -> (a -> b) -> a -> c
. SomeException -> Either SomeException a
forall a b. a -> Either a b
Left (SomeException -> Either SomeException a)
-> (e -> SomeException) -> e -> Either SomeException a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. e -> SomeException
forall e. Exception e => e -> SomeException
toException
instance Monad m => MonadCatch (CatchT m) where
catch :: forall e a.
Exception e =>
CatchT m a -> (e -> CatchT m a) -> CatchT m a
catch (CatchT m (Either SomeException a)
m) e -> CatchT m a
c = m (Either SomeException a) -> CatchT m a
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (m (Either SomeException a) -> CatchT m a)
-> m (Either SomeException a) -> CatchT m a
forall a b. (a -> b) -> a -> b
$ m (Either SomeException a)
m m (Either SomeException a)
-> (Either SomeException a -> m (Either SomeException a))
-> m (Either SomeException a)
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= \Either SomeException a
ea -> case Either SomeException a
ea of
Left SomeException
e -> case SomeException -> Maybe e
forall e. Exception e => SomeException -> Maybe e
fromException SomeException
e of
Just e
e' -> CatchT m a -> m (Either SomeException a)
forall (m :: * -> *) a. CatchT m a -> m (Either SomeException a)
runCatchT (e -> CatchT m a
c e
e')
Maybe e
Nothing -> Either SomeException a -> m (Either SomeException a)
forall (m :: * -> *) a. Monad m => a -> m a
return (SomeException -> Either SomeException a
forall a b. a -> Either a b
Left SomeException
e)
Right a
a -> Either SomeException a -> m (Either SomeException a)
forall (m :: * -> *) a. Monad m => a -> m a
return (a -> Either SomeException a
forall a b. b -> Either a b
Right a
a)
instance Monad m => MonadMask (CatchT m) where
mask :: forall b.
((forall a. CatchT m a -> CatchT m a) -> CatchT m b) -> CatchT m b
mask (forall a. CatchT m a -> CatchT m a) -> CatchT m b
a = (forall a. CatchT m a -> CatchT m a) -> CatchT m b
a forall a. a -> a
forall a. CatchT m a -> CatchT m a
id
uninterruptibleMask :: forall b.
((forall a. CatchT m a -> CatchT m a) -> CatchT m b) -> CatchT m b
uninterruptibleMask (forall a. CatchT m a -> CatchT m a) -> CatchT m b
a = (forall a. CatchT m a -> CatchT m a) -> CatchT m b
a forall a. a -> a
forall a. CatchT m a -> CatchT m a
id
generalBracket :: forall a b c.
CatchT m a
-> (a -> ExitCase b -> CatchT m c)
-> (a -> CatchT m b)
-> CatchT m (b, c)
generalBracket CatchT m a
acquire a -> ExitCase b -> CatchT m c
release a -> CatchT m b
use = m (Either SomeException (b, c)) -> CatchT m (b, c)
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (m (Either SomeException (b, c)) -> CatchT m (b, c))
-> m (Either SomeException (b, c)) -> CatchT m (b, c)
forall a b. (a -> b) -> a -> b
$ do
Either SomeException a
eresource <- CatchT m a -> m (Either SomeException a)
forall (m :: * -> *) a. CatchT m a -> m (Either SomeException a)
runCatchT CatchT m a
acquire
case Either SomeException a
eresource of
Left SomeException
e -> Either SomeException (b, c) -> m (Either SomeException (b, c))
forall (m :: * -> *) a. Monad m => a -> m a
return (Either SomeException (b, c) -> m (Either SomeException (b, c)))
-> Either SomeException (b, c) -> m (Either SomeException (b, c))
forall a b. (a -> b) -> a -> b
$ SomeException -> Either SomeException (b, c)
forall a b. a -> Either a b
Left SomeException
e
Right a
resource -> do
Either SomeException b
eb <- CatchT m b -> m (Either SomeException b)
forall (m :: * -> *) a. CatchT m a -> m (Either SomeException a)
runCatchT (a -> CatchT m b
use a
resource)
case Either SomeException b
eb of
Left SomeException
e -> CatchT m (b, c) -> m (Either SomeException (b, c))
forall (m :: * -> *) a. CatchT m a -> m (Either SomeException a)
runCatchT (CatchT m (b, c) -> m (Either SomeException (b, c)))
-> CatchT m (b, c) -> m (Either SomeException (b, c))
forall a b. (a -> b) -> a -> b
$ do
c
_ <- a -> ExitCase b -> CatchT m c
release a
resource (SomeException -> ExitCase b
forall a. SomeException -> ExitCase a
ExitCaseException SomeException
e)
SomeException -> CatchT m (b, c)
forall (m :: * -> *) e a. (MonadThrow m, Exception e) => e -> m a
throwM SomeException
e
Right b
b -> CatchT m (b, c) -> m (Either SomeException (b, c))
forall (m :: * -> *) a. CatchT m a -> m (Either SomeException a)
runCatchT (CatchT m (b, c) -> m (Either SomeException (b, c)))
-> CatchT m (b, c) -> m (Either SomeException (b, c))
forall a b. (a -> b) -> a -> b
$ do
c
c <- a -> ExitCase b -> CatchT m c
release a
resource (b -> ExitCase b
forall a. a -> ExitCase a
ExitCaseSuccess b
b)
(b, c) -> CatchT m (b, c)
forall (m :: * -> *) a. Monad m => a -> m a
return (b
b, c
c)
instance MonadState s m => MonadState s (CatchT m) where
get :: CatchT m s
get = m s -> CatchT 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 -> CatchT m ()
put = m () -> CatchT m ()
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift (m () -> CatchT m ()) -> (s -> m ()) -> s -> CatchT m ()
forall b c a. (b -> c) -> (a -> b) -> a -> c
. s -> m ()
forall s (m :: * -> *). MonadState s m => s -> m ()
put
#if MIN_VERSION_mtl(2,1,0)
state :: forall a. (s -> (a, s)) -> CatchT m a
state = m a -> CatchT m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift (m a -> CatchT m a)
-> ((s -> (a, s)) -> m a) -> (s -> (a, s)) -> CatchT m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. (s -> (a, s)) -> m a
forall s (m :: * -> *) a. MonadState s m => (s -> (a, s)) -> m a
state
#endif
instance MonadReader e m => MonadReader e (CatchT m) where
ask :: CatchT m e
ask = m e -> CatchT m e
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift m e
forall r (m :: * -> *). MonadReader r m => m r
ask
local :: forall a. (e -> e) -> CatchT m a -> CatchT m a
local e -> e
f (CatchT m (Either SomeException a)
m) = m (Either SomeException a) -> CatchT m a
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT ((e -> e)
-> m (Either SomeException a) -> m (Either SomeException a)
forall r (m :: * -> *) a. MonadReader r m => (r -> r) -> m a -> m a
local e -> e
f m (Either SomeException a)
m)
instance MonadWriter w m => MonadWriter w (CatchT m) where
tell :: w -> CatchT m ()
tell = m () -> CatchT m ()
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift (m () -> CatchT m ()) -> (w -> m ()) -> w -> CatchT m ()
forall b c a. (b -> c) -> (a -> b) -> a -> c
. w -> m ()
forall w (m :: * -> *). MonadWriter w m => w -> m ()
tell
listen :: forall a. CatchT m a -> CatchT m (a, w)
listen = (m (Either SomeException a) -> m (Either SomeException (a, w)))
-> CatchT m a -> CatchT m (a, w)
forall (m :: * -> *) a (n :: * -> *) b.
(m (Either SomeException a) -> n (Either SomeException b))
-> CatchT m a -> CatchT n b
mapCatchT ((m (Either SomeException a) -> m (Either SomeException (a, w)))
-> CatchT m a -> CatchT m (a, w))
-> (m (Either SomeException a) -> m (Either SomeException (a, w)))
-> CatchT m a
-> CatchT m (a, w)
forall a b. (a -> b) -> a -> b
$ \ m (Either SomeException a)
m -> do
(Either SomeException a
a, w
w) <- m (Either SomeException a) -> m (Either SomeException a, w)
forall w (m :: * -> *) a. MonadWriter w m => m a -> m (a, w)
listen m (Either SomeException a)
m
Either SomeException (a, w) -> m (Either SomeException (a, w))
forall (m :: * -> *) a. Monad m => a -> m a
return (Either SomeException (a, w) -> m (Either SomeException (a, w)))
-> Either SomeException (a, w) -> m (Either SomeException (a, w))
forall a b. (a -> b) -> a -> b
$! (a -> (a, w))
-> Either SomeException a -> Either SomeException (a, w)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap (\ a
r -> (a
r, w
w)) Either SomeException a
a
pass :: forall a. CatchT m (a, w -> w) -> CatchT m a
pass = (m (Either SomeException (a, w -> w))
-> m (Either SomeException a))
-> CatchT m (a, w -> w) -> CatchT m a
forall (m :: * -> *) a (n :: * -> *) b.
(m (Either SomeException a) -> n (Either SomeException b))
-> CatchT m a -> CatchT n b
mapCatchT ((m (Either SomeException (a, w -> w))
-> m (Either SomeException a))
-> CatchT m (a, w -> w) -> CatchT m a)
-> (m (Either SomeException (a, w -> w))
-> m (Either SomeException a))
-> CatchT m (a, w -> w)
-> CatchT m a
forall a b. (a -> b) -> a -> b
$ \ m (Either SomeException (a, w -> w))
m -> m (Either SomeException a, w -> w) -> m (Either SomeException a)
forall w (m :: * -> *) a. MonadWriter w m => m (a, w -> w) -> m a
pass (m (Either SomeException a, w -> w) -> m (Either SomeException a))
-> m (Either SomeException a, w -> w) -> m (Either SomeException a)
forall a b. (a -> b) -> a -> b
$ do
Either SomeException (a, w -> w)
a <- m (Either SomeException (a, w -> w))
m
(Either SomeException a, w -> w)
-> m (Either SomeException a, w -> w)
forall (m :: * -> *) a. Monad m => a -> m a
return ((Either SomeException a, w -> w)
-> m (Either SomeException a, w -> w))
-> (Either SomeException a, w -> w)
-> m (Either SomeException a, w -> w)
forall a b. (a -> b) -> a -> b
$! case Either SomeException (a, w -> w)
a of
Left SomeException
l -> (SomeException -> Either SomeException a
forall a b. a -> Either a b
Left SomeException
l, w -> w
forall a. a -> a
id)
Right (a
r, w -> w
f) -> (a -> Either SomeException a
forall a b. b -> Either a b
Right a
r, w -> w
f)
#if MIN_VERSION_mtl(2,1,0)
writer :: forall a. (a, w) -> CatchT m a
writer (a, w)
aw = m (Either SomeException a) -> CatchT m a
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (a -> Either SomeException a
forall a b. b -> Either a b
Right (a -> Either SomeException a) -> m a -> m (Either SomeException a)
forall (m :: * -> *) a1 r. Monad m => (a1 -> r) -> m a1 -> m r
`liftM` (a, w) -> m a
forall w (m :: * -> *) a. MonadWriter w m => (a, w) -> m a
writer (a, w)
aw)
#endif
instance MonadRWS r w s m => MonadRWS r w s (CatchT m)
mapCatchT :: (m (Either SomeException a) -> n (Either SomeException b))
-> CatchT m a
-> CatchT n b
mapCatchT :: forall (m :: * -> *) a (n :: * -> *) b.
(m (Either SomeException a) -> n (Either SomeException b))
-> CatchT m a -> CatchT n b
mapCatchT m (Either SomeException a) -> n (Either SomeException b)
f CatchT m a
m = n (Either SomeException b) -> CatchT n b
forall (m :: * -> *) a. m (Either SomeException a) -> CatchT m a
CatchT (n (Either SomeException b) -> CatchT n b)
-> n (Either SomeException b) -> CatchT n b
forall a b. (a -> b) -> a -> b
$ m (Either SomeException a) -> n (Either SomeException b)
f (CatchT m a -> m (Either SomeException a)
forall (m :: * -> *) a. CatchT m a -> m (Either SomeException a)
runCatchT CatchT m a
m)