Copyright	(c) Andrey Mokhov 2018-2024
License	MIT (see the file LICENSE)
Maintainer	andrey.mokhov@gmail.com
Stability	experimental
Safe Haskell	None
Language	Haskell2010

Control.Selective.Trans.Except

Description

This is a library for selective applicative functors, or just selective functors for short, an abstraction between applicative functors and monads, introduced in this paper: https://dl.acm.org/doi/10.1145/3341694.

This module defines a newtype around ExceptT from transformers with less restrictive Applicative, Selective, and Alternative implementations. It supplies an instance Selective f => Selective (ExceptT e f), which makes ExceptT a bona-fide Selective transformer.

The API follows the API from the transformers package, so it can be used as a drop-in replacement. The documentation can be found in the transformers package.

Synopsis

newtype ExceptT e (f :: Type -> Type) a = ExceptT {
- unwrap :: ExceptT e f a
}
wrap :: forall e (m :: Type -> Type) a. ExceptT e m a -> ExceptT e m a
type Except e = ExceptT e Identity
except :: forall (m :: Type -> Type) e a. Monad m => Either e a -> ExceptT e m a
runExcept :: Except e a -> Either e a
mapExcept :: (Either e a -> Either e' b) -> Except e a -> Except e' b
withExcept :: (e -> e') -> Except e a -> Except e' a
runExceptT :: ExceptT e m a -> m (Either e a)
mapExceptT :: (m (Either e a) -> n (Either e' b)) -> ExceptT e m a -> ExceptT e' n b
withExceptT :: forall (m :: Type -> Type) e e' a. Functor m => (e -> e') -> ExceptT e m a -> ExceptT e' m a
throwE :: forall (m :: Type -> Type) e a. Monad m => e -> ExceptT e m a
catchE :: forall (m :: Type -> Type) e a e'. Monad m => ExceptT e m a -> (e -> ExceptT e' m a) -> ExceptT e' m a
liftCallCC :: CallCC m (Either e a) (Either e b) -> CallCC (ExceptT e m) a b
liftListen :: Monad m => Listen w m (Either e a) -> Listen w (ExceptT e m) a
liftPass :: Monad m => Pass w m (Either e a) -> Pass w (ExceptT e m) a

Documentation

newtype ExceptT e (f :: Type -> Type) a Source #

A newtype wrapper around ExceptT from transformers that provides less restrictive Applicative, Selective and Alternative instances.

Constructors

ExceptT
Fields unwrap :: ExceptT e f a

Instances

Instances details

(Selective f, MonadIO f) => MonadIO (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods liftIO :: IO a -> ExceptT e f a
(Selective f, MonadZip f) => MonadZip (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods mzip :: ExceptT e f a -> ExceptT e f b -> ExceptT e f (a, b) mzipWith :: (a -> b -> c) -> ExceptT e f a -> ExceptT e f b -> ExceptT e f c munzip :: ExceptT e f (a, b) -> (ExceptT e f a, ExceptT e f b)
(Eq1 f, Eq e) => Eq1 (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods liftEq :: (a -> b -> Bool) -> ExceptT e f a -> ExceptT e f b -> Bool
(Ord1 f, Ord e) => Ord1 (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods liftCompare :: (a -> b -> Ordering) -> ExceptT e f a -> ExceptT e f b -> Ordering
(Read1 f, Read e) => Read1 (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (ExceptT e f a) liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [ExceptT e f a] liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (ExceptT e f a) liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [ExceptT e f a]
(Show1 f, Show e) => Show1 (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> ExceptT e f a -> ShowS liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [ExceptT e f a] -> ShowS
Contravariant f => Contravariant (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods contramap :: (a' -> a) -> ExceptT e f a -> ExceptT e f a' (>$) :: b -> ExceptT e f b -> ExceptT e f a
(Selective f, Monoid e) => Alternative (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods empty :: ExceptT e f a (<\|>) :: ExceptT e f a -> ExceptT e f a -> ExceptT e f a some :: ExceptT e f a -> ExceptT e f [a] many :: ExceptT e f a -> ExceptT e f [a]
Selective f => Applicative (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods pure :: a -> ExceptT e f a (<>) :: ExceptT e f (a -> b) -> ExceptT e f a -> ExceptT e f b liftA2 :: (a -> b -> c) -> ExceptT e f a -> ExceptT e f b -> ExceptT e f c (>) :: ExceptT e f a -> ExceptT e f b -> ExceptT e f b (<*) :: ExceptT e f a -> ExceptT e f b -> ExceptT e f a
Functor f => Functor (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods fmap :: (a -> b) -> ExceptT e f a -> ExceptT e f b (<$) :: a -> ExceptT e f b -> ExceptT e f a
(Selective f, Monad f) => Monad (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods (>>=) :: ExceptT e f a -> (a -> ExceptT e f b) -> ExceptT e f b (>>) :: ExceptT e f a -> ExceptT e f b -> ExceptT e f b return :: a -> ExceptT e f a
(Selective f, Monoid e, Monad f) => MonadPlus (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods mzero :: ExceptT e f a mplus :: ExceptT e f a -> ExceptT e f a -> ExceptT e f a
(Selective f, MonadFail f) => MonadFail (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods fail :: String -> ExceptT e f a
(Selective f, MonadFix f) => MonadFix (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods mfix :: (a -> ExceptT e f a) -> ExceptT e f a
Foldable f => Foldable (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods fold :: Monoid m => ExceptT e f m -> m foldMap :: Monoid m => (a -> m) -> ExceptT e f a -> m foldMap' :: Monoid m => (a -> m) -> ExceptT e f a -> m foldr :: (a -> b -> b) -> b -> ExceptT e f a -> b foldr' :: (a -> b -> b) -> b -> ExceptT e f a -> b foldl :: (b -> a -> b) -> b -> ExceptT e f a -> b foldl' :: (b -> a -> b) -> b -> ExceptT e f a -> b foldr1 :: (a -> a -> a) -> ExceptT e f a -> a foldl1 :: (a -> a -> a) -> ExceptT e f a -> a toList :: ExceptT e f a -> [a] null :: ExceptT e f a -> Bool length :: ExceptT e f a -> Int elem :: Eq a => a -> ExceptT e f a -> Bool maximum :: Ord a => ExceptT e f a -> a minimum :: Ord a => ExceptT e f a -> a sum :: Num a => ExceptT e f a -> a product :: Num a => ExceptT e f a -> a
Traversable f => Traversable (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods traverse :: Applicative f0 => (a -> f0 b) -> ExceptT e f a -> f0 (ExceptT e f b) sequenceA :: Applicative f0 => ExceptT e f (f0 a) -> f0 (ExceptT e f a) mapM :: Monad m => (a -> m b) -> ExceptT e f a -> m (ExceptT e f b) sequence :: Monad m => ExceptT e f (m a) -> m (ExceptT e f a)
Selective f => Selective (ExceptT e f) Source #
Instance details Defined in Control.Selective.Trans.Except Methods select :: ExceptT e f (Either a b) -> ExceptT e f (a -> b) -> ExceptT e f b Source #
(Read1 f, Read e, Read a) => Read (ExceptT e f a) Source #
Instance details Defined in Control.Selective.Trans.Except Methods readsPrec :: Int -> ReadS (ExceptT e f a) readList :: ReadS [ExceptT e f a] readPrec :: ReadPrec (ExceptT e f a) readListPrec :: ReadPrec [ExceptT e f a]
(Show1 f, Show e, Show a) => Show (ExceptT e f a) Source #
Instance details Defined in Control.Selective.Trans.Except Methods showsPrec :: Int -> ExceptT e f a -> ShowS show :: ExceptT e f a -> String showList :: [ExceptT e f a] -> ShowS
(Eq1 f, Eq e, Eq a) => Eq (ExceptT e f a) Source #
Instance details Defined in Control.Selective.Trans.Except Methods (==) :: ExceptT e f a -> ExceptT e f a -> Bool (/=) :: ExceptT e f a -> ExceptT e f a -> Bool
(Ord1 f, Ord e, Ord a) => Ord (ExceptT e f a) Source #
Instance details Defined in Control.Selective.Trans.Except Methods compare :: ExceptT e f a -> ExceptT e f a -> Ordering (<) :: ExceptT e f a -> ExceptT e f a -> Bool (<=) :: ExceptT e f a -> ExceptT e f a -> Bool (>) :: ExceptT e f a -> ExceptT e f a -> Bool (>=) :: ExceptT e f a -> ExceptT e f a -> Bool max :: ExceptT e f a -> ExceptT e f a -> ExceptT e f a min :: ExceptT e f a -> ExceptT e f a -> ExceptT e f a

wrap :: forall e (m :: Type -> Type) a. ExceptT e m a -> ExceptT e m a Source #

Inject an ExceptT value into the newtype wrapper.

type Except e = ExceptT e Identity Source #

except :: forall (m :: Type -> Type) e a. Monad m => Either e a -> ExceptT e m a Source #

runExcept :: Except e a -> Either e a Source #

mapExcept :: (Either e a -> Either e' b) -> Except e a -> Except e' b Source #

withExcept :: (e -> e') -> Except e a -> Except e' a Source #

runExceptT :: ExceptT e m a -> m (Either e a) Source #

mapExceptT :: (m (Either e a) -> n (Either e' b)) -> ExceptT e m a -> ExceptT e' n b Source #

withExceptT :: forall (m :: Type -> Type) e e' a. Functor m => (e -> e') -> ExceptT e m a -> ExceptT e' m a Source #

throwE :: forall (m :: Type -> Type) e a. Monad m => e -> ExceptT e m a Source #

catchE :: forall (m :: Type -> Type) e a e'. Monad m => ExceptT e m a -> (e -> ExceptT e' m a) -> ExceptT e' m a Source #

liftCallCC :: CallCC m (Either e a) (Either e b) -> CallCC (ExceptT e m) a b Source #

liftListen :: Monad m => Listen w m (Either e a) -> Listen w (ExceptT e m) a Source #

liftPass :: Monad m => Pass w m (Either e a) -> Pass w (ExceptT e m) a Source #