Copyright	(c) 2023-2025 Sayo contributors
License	MPL-2.0 (see the file LICENSE)
Maintainer	ymdfield@outlook.jp
Safe Haskell	Safe-Inferred
Language	GHC2021

Data.Effect.Except

Description

An effect to escape from the normal control structure with an exception value in the middle of a context.

Synopsis

throw :: forall (e :: Type) (b :: Type) a es ff c. (Free c ff, a ~ Eff ff es, (:>) (Throw e) es) => e -> a b
catch :: forall (b :: Type) (e :: Type) a es ff c. (Free c ff, a ~ Eff ff es, (:>) (Catch e) es) => a b -> (e -> a b) -> a b
withExcept :: forall e es a ff c. (Catch e :> es, Throw e :> es, Applicative (Eff ff es), Free c ff) => Eff ff es a -> (e -> Eff ff es ()) -> Eff ff es a
liftEither :: forall e es a ff c. (Throw e :> es, Applicative (Eff ff es), Free c ff) => Either e a -> Eff ff es a
joinEither :: forall e es a ff c. (Throw e :> es, Monad (Eff ff es), Free c ff) => Eff ff es (Either e a) -> Eff ff es a
joinExcept :: Monad m => Either (m a) a -> m a
exc :: Monad m => m (Either (m a) a) -> m a
onExcept :: forall e es ff a c. (Catch e :> es, Throw e :> es, Applicative (Eff ff es), Free c ff) => Eff ff es a -> Eff ff es () -> Eff ff es a
runThrowIO :: forall e es ff a c. (Emb IO :> es, Exception e, Monad (Eff ff es), Free c ff) => Eff ff (Throw e ': es) a -> Eff ff es a
runCatchIO :: forall e es ff a c. (UnliftIO :> es, Emb IO :> es, Exception e, Monad (Eff ff es), Free c ff) => Eff ff (Catch e ': es) a -> Eff ff es a
throw' :: forall key (e :: Type) (b :: Type) a es ff c. (Free c ff, a ~ Eff ff es, Has key (Throw e) es) => e -> a b
throw'' :: forall tag (e :: Type) (b :: Type) a es ff c. (Free c ff, a ~ Eff ff es, (:>) (Tagged tag (Throw e)) es) => e -> a b
throw'_ :: forall (e :: Type) (b :: Type) a es ff c. (Free c ff, a ~ Eff ff es, In (Throw e) es) => e -> a b
catch' :: forall key (b :: Type) (e :: Type) a es ff c. (Free c ff, a ~ Eff ff es, Has key (Catch e) es) => a b -> (e -> a b) -> a b
catch'' :: forall tag (b :: Type) (e :: Type) a es ff c. (Free c ff, a ~ Eff ff es, (:>) (Tagged tag (Catch e)) es) => a b -> (e -> a b) -> a b
catch'_ :: forall (b :: Type) (e :: Type) a es ff c. (Free c ff, a ~ Eff ff es, In (Catch e) es) => a b -> (e -> a b) -> a b
data Catch e (a :: Type -> Type) b where
- Catch :: forall (a :: Type -> Type) b e. a b -> (e -> a b) -> Catch e a b
data Throw e (a :: Type -> Type) b where
- Throw :: forall e (a :: Type -> Type) b. e -> Throw e a b

Documentation

throw :: forall (e :: Type) (b :: Type) a es ff c. (Free c ff, a ~ Eff ff es, (:>) (Throw e) es) => e -> a b Source #

catch :: forall (b :: Type) (e :: Type) a es ff c. (Free c ff, a ~ Eff ff es, (:>) (Catch e) es) => a b -> (e -> a b) -> a b Source #

withExcept Source #

Arguments

:: forall e es a ff c. (Catch e :> es, Throw e :> es, Applicative (Eff ff es), Free c ff)
=> Eff ff es a	Scope to which the exception handler applies
-> (e -> Eff ff es ())	Exception handler
-> Eff ff es a

If an exception occurs, executes the given exception handler, but the exception is not stopped there and is rethrown.

liftEither :: forall e es a ff c. (Throw e :> es, Applicative (Eff ff es), Free c ff) => Either e a -> Eff ff es a Source #

Throws the given Either value as an exception if it is Left.

joinEither :: forall e es a ff c. (Throw e :> es, Monad (Eff ff es), Free c ff) => Eff ff es (Either e a) -> Eff ff es a Source #

Throws the result of the given action as an exception if it is Left.

joinExcept :: Monad m => Either (m a) a -> m a Source #

If the given Either value is Left, execute it as an action.

exc :: Monad m => m (Either (m a) a) -> m a Source #

If the result of the given action is Left, execute it as an action.

onExcept Source #

Arguments

:: forall e es ff a c. (Catch e :> es, Throw e :> es, Applicative (Eff ff es), Free c ff)
=> Eff ff es a	Scope in which to detect exceptions
-> Eff ff es ()	Action to execute in case of an exception
-> Eff ff es a

If an exception occurs, executes the specified action, but the exception is not stopped there and is rethrown.

runThrowIO :: forall e es ff a c. (Emb IO :> es, Exception e, Monad (Eff ff es), Free c ff) => Eff ff (Throw e ': es) a -> Eff ff es a Source #

Interpret the Throw effect based on an IO-fused semantics using IO-level exceptions.

runCatchIO :: forall e es ff a c. (UnliftIO :> es, Emb IO :> es, Exception e, Monad (Eff ff es), Free c ff) => Eff ff (Catch e ': es) a -> Eff ff es a Source #

Interpret the Catch effect based on an IO-fused semantics using IO-level exceptions.

throw' :: forall key (e :: Type) (b :: Type) a es ff c. (Free c ff, a ~ Eff ff es, Has key (Throw e) es) => e -> a b Source #

throw'' :: forall tag (e :: Type) (b :: Type) a es ff c. (Free c ff, a ~ Eff ff es, (:>) (Tagged tag (Throw e)) es) => e -> a b Source #

throw'_ :: forall (e :: Type) (b :: Type) a es ff c. (Free c ff, a ~ Eff ff es, In (Throw e) es) => e -> a b Source #

catch' :: forall key (b :: Type) (e :: Type) a es ff c. (Free c ff, a ~ Eff ff es, Has key (Catch e) es) => a b -> (e -> a b) -> a b Source #

catch'' :: forall tag (b :: Type) (e :: Type) a es ff c. (Free c ff, a ~ Eff ff es, (:>) (Tagged tag (Catch e)) es) => a b -> (e -> a b) -> a b Source #

catch'_ :: forall (b :: Type) (e :: Type) a es ff c. (Free c ff, a ~ Eff ff es, In (Catch e) es) => a b -> (e -> a b) -> a b Source #

data Catch e (a :: Type -> Type) b where #

An effect to catch exceptions.

Constructors

Catch	Catches exceptions within a scope and processes them according to the given exception handler.
Fields :: forall (a :: Type -> Type) b e. a b The scope in which to catch exceptions. -> (e -> a b) Exception handler. Defines the processing to perform when an exception is thrown within the scope. -> Catch e a b

Instances

Instances details

HFunctor (Catch w)
Instance details Defined in Data.Effect Methods hfmap :: (forall x. f x -> g x) -> Catch w f a -> Catch w g a #
type LabelOf (Catch w)
Instance details Defined in Data.Effect type LabelOf (Catch w) = CatchLabel
type OrderOf (Catch w)
Instance details Defined in Data.Effect type OrderOf (Catch w) = 'HigherOrder

data Throw e (a :: Type -> Type) b where #

An effect to escape from the normal control structure with an exception value of type e in the middle of a context.

Constructors

Throw :: forall e (a :: Type -> Type) b. e -> Throw e a b

Throws an exception; that is, escapes from the normal control structure with an exception value in the middle of a context.

Instances

Instances details

FirstOrder (Throw e)
Instance details Defined in Data.Effect
HFunctor (Throw e)
Instance details Defined in Data.Effect Methods hfmap :: (forall x. f x -> g x) -> Throw e f a -> Throw e g a #
type LabelOf (Throw e)
Instance details Defined in Data.Effect type LabelOf (Throw e) = ThrowLabel
type OrderOf (Throw e)
Instance details Defined in Data.Effect type OrderOf (Throw e) = 'FirstOrder