Safe Haskell	Safe
Language	Haskell98

Control.Proxy.Trans.Either

Contents

EitherP
Either operations
Symmetric monad

Description

This module provides the proxy transformer equivalent of EitherT.

Synopsis

EitherP

newtype EitherP e p a' a b' b m r Source #

The Either proxy transformer

Constructors

EitherP
Fields runEitherP :: p a' a b' b m (Either e r)

Instances

ProxyTrans (EitherP e) Source #
Methods liftP :: (Monad m, Proxy p) => p a' a b' b m r -> EitherP e p a' a b' b m r Source #
PFunctor (EitherP e) Source #
Methods hoistP :: (Monad m, Proxy p) => (forall a' a b' b r1. p a' a b' b m r1 -> q a' a b' b m r1) -> EitherP e p a' a b' b m r2 -> EitherP e q a' a b' b m r2 Source #
MonadIOP p => MonadIOP (EitherP e p) Source #
Methods liftIO_P :: MonadIO m => IO r -> EitherP e p a' a b' b m r Source #
MonadPlusP p => MonadPlusP (EitherP e p) Source #
Methods mzero_P :: Monad m => EitherP e p a' a b' b m r Source # mplus_P :: Monad m => EitherP e p a' a b' b m r -> EitherP e p a' a b' b m r -> EitherP e p a' a b' b m r Source #
Proxy p => Proxy (EitherP e p) Source #
Methods request :: Monad m => a' -> EitherP e p a' a b' b m a Source # respond :: Monad m => b -> EitherP e p a' a b' b m b' Source # (>->) :: Monad m => (b' -> EitherP e p a' a b' b m r) -> (c' -> EitherP e p b' b c' c m r) -> c' -> EitherP e p a' a c' c m r Source # (>~>) :: Monad m => (a -> EitherP e p a' a b' b m r) -> (b -> EitherP e p b' b c' c m r) -> a -> EitherP e p a' a c' c m r Source # return_P :: Monad m => r -> EitherP e p a' a b' b m r Source # (?>=) :: Monad m => EitherP e p a' a b' b m r -> (r -> EitherP e p a' a b' b m r') -> EitherP e p a' a b' b m r' Source # lift_P :: Monad m => m r -> EitherP e p a' a b' b m r Source # hoist_P :: Monad m => (forall r. m r -> n r) -> EitherP e p a' a b' b m r' -> EitherP e p a' a b' b n r' Source #
Proxy p => MonadTrans (EitherP e p a' a b' b) Source #
Methods lift :: Monad m => m a -> EitherP e p a' a b' b m a #
Proxy p => MFunctor (EitherP e p a' a b' b) Source #
Methods hoist :: Monad m => (forall c. m c -> n c) -> EitherP e p a' a b' b m b -> EitherP e p a' a b' b n b Source #
(Proxy p, Monad m) => Monad (EitherP e p a' a b' b m) Source #
Methods (>>=) :: EitherP e p a' a b' b m a -> (a -> EitherP e p a' a b' b m b) -> EitherP e p a' a b' b m b # (>>) :: EitherP e p a' a b' b m a -> EitherP e p a' a b' b m b -> EitherP e p a' a b' b m b # return :: a -> EitherP e p a' a b' b m a # fail :: String -> EitherP e p a' a b' b m a #
(Proxy p, Monad m) => Functor (EitherP e p a' a b' b m) Source #
Methods fmap :: (a -> b) -> EitherP e p a' a b' b m a -> EitherP e p a' a b' b m b # (<$) :: a -> EitherP e p a' a b' b m b -> EitherP e p a' a b' b m a #
(Proxy p, Monad m) => Applicative (EitherP e p a' a b' b m) Source #
Methods pure :: a -> EitherP e p a' a b' b m a # (<>) :: EitherP e p a' a b' b m (a -> b) -> EitherP e p a' a b' b m a -> EitherP e p a' a b' b m b # (>) :: EitherP e p a' a b' b m a -> EitherP e p a' a b' b m b -> EitherP e p a' a b' b m b # (<*) :: EitherP e p a' a b' b m a -> EitherP e p a' a b' b m b -> EitherP e p a' a b' b m a #
(MonadIOP p, MonadIO m) => MonadIO (EitherP e p a' a b' b m) Source #
Methods liftIO :: IO a -> EitherP e p a' a b' b m a #
(MonadPlusP p, Monad m) => Alternative (EitherP e p a' a b' b m) Source #
Methods empty :: EitherP e p a' a b' b m a # (<\|>) :: EitherP e p a' a b' b m a -> EitherP e p a' a b' b m a -> EitherP e p a' a b' b m a # some :: EitherP e p a' a b' b m a -> EitherP e p a' a b' b m [a] # many :: EitherP e p a' a b' b m a -> EitherP e p a' a b' b m [a] #
(MonadPlusP p, Monad m) => MonadPlus (EitherP e p a' a b' b m) Source #
Methods mzero :: EitherP e p a' a b' b m a # mplus :: EitherP e p a' a b' b m a -> EitherP e p a' a b' b m a -> EitherP e p a' a b' b m a #

runEitherK :: (q -> EitherP e p a' a b' b m r) -> q -> p a' a b' b m (Either e r) Source #

Run an EitherP 'K'leisi arrow, returning either a Left or Right

Either operations

left :: (Monad m, Proxy p) => e -> EitherP e p a' a b' b m r Source #

Abort the computation and return a Left result

right :: (Monad m, Proxy p) => r -> EitherP e p a' a b' b m r Source #

Synonym for return

Symmetric monad

EitherP forms a second symmetric monad over the left type variable.

throw is symmetric to return

catch is symmetric to (>>=)

These two functions obey the monad laws:

catch m throw = m

catch (throw e) f = f e

catch (catch m f) g = catch m (\e -> catch (f e) g)

throw :: (Monad m, Proxy p) => e -> EitherP e p a' a b' b m r Source #

Synonym for left

catch Source #

Arguments

:: (Monad m, Proxy p)
=> EitherP e p a' a b' b m r	Original computation
-> (e -> EitherP f p a' a b' b m r)	Handler
-> EitherP f p a' a b' b m r	Handled computation

Resume from an aborted operation

handle Source #

Arguments

:: (Monad m, Proxy p)
=> (e -> EitherP f p a' a b' b m r)	Handler
-> EitherP e p a' a b' b m r	Original computation
-> EitherP f p a' a b' b m r	Handled computation

catch with the arguments flipped