Copyright	(c) 2019 Yann Herklotz Grave
License	GPL-3
Maintainer	yann [at] yannherklotz [dot] com
Stability	experimental
Portability	POSIX
Safe Haskell	None
Language	Haskell2010

Verismith.Result

Description

Result monadic type. This is nearly equivalent to the transformers Error type, but to have more control this is reimplemented with the instances that are needed in Verismith.

Synopsis

data Result a b
- = Fail a
- | Pass b
newtype ResultT a (m :: Type -> Type) b = ResultT {
- runResultT :: m (Result a b)
}
justPass :: Result a b -> Maybe b
justFail :: Result a b -> Maybe a
(<?>) :: forall (m :: Type -> Type) a b. (Monad m, Monoid a) => ResultT a m b -> a -> ResultT a m b
annotate :: forall (m :: Type -> Type) a b. (Monad m, Monoid a) => a -> ResultT a m b -> ResultT a m b

Documentation

data Result a b Source #

Result type which is equivalent to Either or Error. This is reimplemented so that there is full control over the Monad definition and definition of a Monad transformer ResultT.

Constructors

Fail a
Pass b

Instances

Instances details

Bifunctor Result Source #
Instance details Defined in Verismith.Result Methods bimap :: (a -> b) -> (c -> d) -> Result a c -> Result b d # first :: (a -> b) -> Result a c -> Result b c # second :: (b -> c) -> Result a b -> Result a c #
Applicative (Result a) Source #
Instance details Defined in Verismith.Result Methods pure :: a0 -> Result a a0 # (<>) :: Result a (a0 -> b) -> Result a a0 -> Result a b # liftA2 :: (a0 -> b -> c) -> Result a a0 -> Result a b -> Result a c # (>) :: Result a a0 -> Result a b -> Result a b # (<*) :: Result a a0 -> Result a b -> Result a a0 #
Functor (Result a) Source #
Instance details Defined in Verismith.Result Methods fmap :: (a0 -> b) -> Result a a0 -> Result a b # (<$) :: a0 -> Result a b -> Result a a0 #
Monad (Result a) Source #
Instance details Defined in Verismith.Result Methods (>>=) :: Result a a0 -> (a0 -> Result a b) -> Result a b # (>>) :: Result a a0 -> Result a b -> Result a b # return :: a0 -> Result a a0 #
MonadBase (Result a) (Result a) Source #
Instance details Defined in Verismith.Result Methods liftBase :: Result a α -> Result a α #
Monoid b => Monoid (Result a b) Source #
Instance details Defined in Verismith.Result Methods mempty :: Result a b # mappend :: Result a b -> Result a b -> Result a b # mconcat :: [Result a b] -> Result a b #
Semigroup (Result a b) Source #
Instance details Defined in Verismith.Result Methods (<>) :: Result a b -> Result a b -> Result a b # sconcat :: NonEmpty (Result a b) -> Result a b # stimes :: Integral b0 => b0 -> Result a b -> Result a b #
(Show a, Show b) => Show (Result a b) Source #
Instance details Defined in Verismith.Result Methods showsPrec :: Int -> Result a b -> ShowS # show :: Result a b -> String # showList :: [Result a b] -> ShowS #
(Eq a, Eq b) => Eq (Result a b) Source #
Instance details Defined in Verismith.Result Methods (==) :: Result a b -> Result a b -> Bool # (/=) :: Result a b -> Result a b -> Bool #

newtype ResultT a (m :: Type -> Type) b Source #

The transformer for the Result type. This

Constructors

ResultT
Fields runResultT :: m (Result a b)

Instances

Instances details

MonadBaseControl IO m => MonadBaseControl IO (ResultT a m) Source #
Instance details Defined in Verismith.Result Methods liftBaseWith :: (RunInBase (ResultT a m) IO -> IO a0) -> ResultT a m a0 # restoreM :: StM (ResultT a m) a0 -> ResultT a m a0 #
MonadBase b m => MonadBase b (ResultT a m) Source #
Instance details Defined in Verismith.Result Methods liftBase :: b α -> ResultT a m α #
MonadTransControl (ResultT a) Source #
Instance details Defined in Verismith.Result Methods liftWith :: Monad m => (Run (ResultT a) -> m a0) -> ResultT a m a0 # restoreT :: Monad m => m (StT (ResultT a) a0) -> ResultT a m a0 #
MonadTrans (ResultT e) Source #
Instance details Defined in Verismith.Result Methods lift :: Monad m => m a -> ResultT e m a #
MonadIO m => MonadIO (ResultT a m) Source #
Instance details Defined in Verismith.Result Methods liftIO :: IO a0 -> ResultT a m a0 #
Monad m => Applicative (ResultT a m) Source #
Instance details Defined in Verismith.Result Methods pure :: a0 -> ResultT a m a0 # (<>) :: ResultT a m (a0 -> b) -> ResultT a m a0 -> ResultT a m b # liftA2 :: (a0 -> b -> c) -> ResultT a m a0 -> ResultT a m b -> ResultT a m c # (>) :: ResultT a m a0 -> ResultT a m b -> ResultT a m b # (<*) :: ResultT a m a0 -> ResultT a m b -> ResultT a m a0 #
Functor f => Functor (ResultT a f) Source #
Instance details Defined in Verismith.Result Methods fmap :: (a0 -> b) -> ResultT a f a0 -> ResultT a f b # (<$) :: a0 -> ResultT a f b -> ResultT a f a0 #
Monad m => Monad (ResultT a m) Source #
Instance details Defined in Verismith.Result Methods (>>=) :: ResultT a m a0 -> (a0 -> ResultT a m b) -> ResultT a m b # (>>) :: ResultT a m a0 -> ResultT a m b -> ResultT a m b # return :: a0 -> ResultT a m a0 #
(MonadSh m, Monoid a) => MonadSh (ResultT a m) Source #
Instance details Defined in Verismith.Result Methods liftSh :: Sh a0 -> ResultT a m a0 #
MonadShControl m => MonadShControl (ResultT a m) Source #
Instance details Defined in Verismith.Result Methods liftShWith :: ((forall x. ResultT a m x -> Sh (ShM (ResultT a m) x)) -> Sh a0) -> ResultT a m a0 # restoreSh :: ShM (ResultT a m) a0 -> ResultT a m a0 #
type StT (ResultT a) b Source #
Instance details Defined in Verismith.Result type StT (ResultT a) b = Result a b
newtype ShM (ResultT a m) b Source #
Instance details Defined in Verismith.Result newtype ShM (ResultT a m) b = ResultTShM (ShM m (Result a b))
type StM (ResultT a m) b Source #
Instance details Defined in Verismith.Result type StM (ResultT a m) b = ComposeSt (ResultT a) m b

justPass :: Result a b -> Maybe b Source #

justFail :: Result a b -> Maybe a Source #

(<?>) :: forall (m :: Type -> Type) a b. (Monad m, Monoid a) => ResultT a m b -> a -> ResultT a m b infix 0 Source #

annotate :: forall (m :: Type -> Type) a b. (Monad m, Monoid a) => a -> ResultT a m b -> ResultT a m b Source #