Safe Haskell	None
Language	Haskell2010

Control.Effect.Type.Mask

Contents

Effects
Threading utilities

Synopsis

data Mask m a where
- Mask :: MaskMode -> ((forall x. m x -> m x) -> m a) -> Mask m a
data MaskMode
- = InterruptibleMask
- | UninterruptibleMask
threadMaskViaClass :: forall t m a. Monad m => (RepresentationalT t, forall b. MonadMask b => MonadMask (t b)) => (forall x. Mask m x -> m x) -> Mask (t m) a -> t m a

Effects

data Mask m a where Source #

An effect for masking asynchronous exceptions.

Mask is typically used as a primitive effect. If you define a Carrier that relies on a novel non-trivial monad transformer t, then you need to make a ThreadsEff t Mask instance (if possible). threadMaskViaClass can help you with that.

The following threading constraints accept Mask:

Constructors

Mask :: MaskMode -> ((forall x. m x -> m x) -> m a) -> Mask m a

Instances

ThreadsEff (ExceptT e) (Mask :: (Type -> Type) -> Type -> Type) Source #
Instance details Defined in Control.Effect.Type.Mask Methods threadEff :: Monad m => (forall x. Mask m x -> m x) -> Mask (ExceptT e m) a -> ExceptT e m a Source #
Monoid s => ThreadsEff (WriterT s) (Mask :: (Type -> Type) -> Type -> Type) Source #
Instance details Defined in Control.Effect.Type.Mask Methods threadEff :: Monad m => (forall x. Mask m x -> m x) -> Mask (WriterT s m) a -> WriterT s m a Source #
ThreadsEff (StateT s) (Mask :: (Type -> Type) -> Type -> Type) Source #
Instance details Defined in Control.Effect.Type.Mask Methods threadEff :: Monad m => (forall x. Mask m x -> m x) -> Mask (StateT s m) a -> StateT s m a Source #
ThreadsEff (ReaderT i) (Mask :: (Type -> Type) -> Type -> Type) Source #
Instance details Defined in Control.Effect.Type.Mask Methods threadEff :: Monad m => (forall x. Mask m x -> m x) -> Mask (ReaderT i m) a -> ReaderT i m a Source #
ThreadsEff (StateT s) (Mask :: (Type -> Type) -> Type -> Type) Source #
Instance details Defined in Control.Effect.Type.Mask Methods threadEff :: Monad m => (forall x. Mask m x -> m x) -> Mask (StateT s m) a -> StateT s m a Source #
Monoid s => ThreadsEff (WriterT s) (Mask :: (Type -> Type) -> Type -> Type) Source #
Instance details Defined in Control.Effect.Type.Mask Methods threadEff :: Monad m => (forall x. Mask m x -> m x) -> Mask (WriterT s m) a -> WriterT s m a Source #
Monoid s => ThreadsEff (WriterT s) (Mask :: (Type -> Type) -> Type -> Type) Source #
Instance details Defined in Control.Effect.Type.Mask Methods threadEff :: Monad m => (forall x. Mask m x -> m x) -> Mask (WriterT s m) a -> WriterT s m a Source #
Monad m => MonadThrow (ViaAlg s (Mask :: (Type -> Type) -> Type -> Type) m) Source #
Instance details Defined in Control.Effect.Type.Mask Methods throwM :: Exception e => e -> ViaAlg s Mask m a #
Monad m => MonadCatch (ViaAlg s (Mask :: (Type -> Type) -> Type -> Type) m) Source #
Instance details Defined in Control.Effect.Type.Mask Methods catch :: Exception e => ViaAlg s Mask m a -> (e -> ViaAlg s Mask m a) -> ViaAlg s Mask m a #
(Reifies s (ReifiedEffAlgebra (Mask :: (Type -> Type) -> Type -> Type) m), Monad m) => MonadMask (ViaAlg s (Mask :: (Type -> Type) -> Type -> Type) m) Source #
Instance details Defined in Control.Effect.Type.Mask Methods mask :: ((forall a. ViaAlg s Mask m a -> ViaAlg s Mask m a) -> ViaAlg s Mask m b) -> ViaAlg s Mask m b # uninterruptibleMask :: ((forall a. ViaAlg s Mask m a -> ViaAlg s Mask m a) -> ViaAlg s Mask m b) -> ViaAlg s Mask m b # generalBracket :: ViaAlg s Mask m a -> (a -> ExitCase b -> ViaAlg s Mask m c) -> (a -> ViaAlg s Mask m b) -> ViaAlg s Mask m (b, c) #

data MaskMode Source #

Constructors

InterruptibleMask
UninterruptibleMask

Threading utilities

threadMaskViaClass :: forall t m a. Monad m => (RepresentationalT t, forall b. MonadMask b => MonadMask (t b)) => (forall x. Mask m x -> m x) -> Mask (t m) a -> t m a Source #

A valid definition of threadEff for a ThreadsEff t Mask instance, given that t lifts MonadMask.

BEWARE: threadMaskViaClass is only safe if the implementation of mask and uninterruptibleMask for t m only makes use of mask and uninterruptibleMask for m, and no other methods of MonadThrow, MonadCatch, and MonadMask.