Safe Haskell	None
Language	Haskell2010

Effectful.Fail

Contents

Description

Provider of the MonadFail instance for Eff.

Synopsis

data Fail (a :: Type -> Type) b where
- Fail :: forall (a :: Type -> Type) b. String -> Fail a b
runFail :: forall (es :: [(Type -> Type) -> Type -> Type]) a. HasCallStack => Eff (Fail ': es) a -> Eff es (Either String a)
runFailIO :: forall (es :: [Effect]) a. (HasCallStack, IOE :> es) => Eff (Fail ': es) a -> Eff es a

Effect

data Fail (a :: Type -> Type) b where Source #

Provide the ability to use the MonadFail instance for Eff.

Constructors

Fail :: forall (a :: Type -> Type) b. String -> Fail a b

Instances details

type DispatchOf Fail Source #
Instance details Defined in Effectful.Internal.Monad type DispatchOf Fail = 'Dynamic

Handlers

runFail :: forall (es :: [(Type -> Type) -> Type -> Type]) a. HasCallStack => Eff (Fail ': es) a -> Eff es (Either String a) Source #

Run the Fail effect via Error.

runFailIO :: forall (es :: [Effect]) a. (HasCallStack, IOE :> es) => Eff (Fail ': es) a -> Eff es a Source #

Run the Fail effect via the MonadFail instance for IO.