Control.Monad.Trans.MSF.Except

Throwing exceptions

throwOnCond :: Monad m => (a -> Bool) -> e -> MSF (ExceptT e m) a a

throwOnCondM :: Monad m => (a -> m Bool) -> e -> MSF (ExceptT e m) a a

throwOn :: Monad m => e -> MSF (ExceptT e m) Bool ()

throwOn' :: Monad m => MSF (ExceptT e m) (Bool, e) ()

throwMaybe :: Monad m => MSF (ExceptT e m) (Maybe e) (Maybe a)

throwS :: Monad m => MSF (ExceptT e m) e a

throw :: Monad m => e -> MSF (ExceptT e m) a b

pass :: Monad m => MSF (ExceptT e m) a a

maybeToExceptS :: Monad m => MSF (MaybeT m) a b -> MSF (ExceptT () m) a b

Whenever Nothing is thrown, throw '()' instead.

Catching exceptions

catchS :: Monad m => MSF (ExceptT e m) a b -> (e -> MSF m a b) -> MSF m a b

untilE :: Monad m => MSF m a b -> MSF m b (Maybe e) -> MSF (ExceptT e m) a b

exceptS :: Monad m => MSF (ExceptT e m) a b -> MSF m a (Either e b)

inExceptT :: Monad m => MSF (ExceptT e m) (ExceptT e m a) a

Monad interface for Exception MSFs

newtype MSFExcept m a b e

Constructors

MSFExcept

Fields

• runMSFExcept :: MSF (ExceptT e m) a b

Instances

Monad m => Monad (MSFExcept m a b)

Methods

(>>=) :: MSFExcept m a b a -> (a -> MSFExcept m a b b) -> MSFExcept m a b b

(>>) :: MSFExcept m a b a -> MSFExcept m a b b -> MSFExcept m a b b

return :: a -> MSFExcept m a b a

fail :: String -> MSFExcept m a b a

Monad m => Functor (MSFExcept m a b)

Methods

fmap :: (a -> b) -> MSFExcept m a b a -> MSFExcept m a b b

(<$) :: a -> MSFExcept m a b b -> MSFExcept m a b a

Monad m => Applicative (MSFExcept m a b)

Methods

pure :: a -> MSFExcept m a b a

(<*>) :: MSFExcept m a b (a -> b) -> MSFExcept m a b a -> MSFExcept m a b b

(*>) :: MSFExcept m a b a -> MSFExcept m a b b -> MSFExcept m a b b

(<*) :: MSFExcept m a b a -> MSFExcept m a b b -> MSFExcept m a b a

try :: MSF (ExceptT e m) a b -> MSFExcept m a b e

currentInput :: Monad m => MSFExcept m e b e

Immediately throw the current input as an exception.

data Empty

safely :: Monad m => MSFExcept m a b Empty -> MSF m a b

safe :: Monad m => MSF m a b -> MSFExcept m a b e

once :: Monad m => (a -> m e) -> MSFExcept m a b e

once_ :: Monad m => m e -> MSFExcept m a b e

step :: Monad m => (a -> m (b, e)) -> MSFExcept m a b e

Advances a single tick with the given Kleisli arrow, and then throws an exception.

tagged :: Monad m => MSF (ExceptT e1 m) a b -> MSF (ExceptT e2 m) (a, e2) b

module Control.Monad.Trans.Except