Control.Monad.Resource.Trans

newtype ResourceT (m :: Type -> Type) a

The resource cleanup monad transformer.

This monad transformer extends the base monad with a mutable registry for tracking resource cleanup actions. At the end of evaluation all remaining cleanup actions are executed.

Constructors

• ResourceT (Registry -> m a)

Instances

• (Functor m) => Functor (ResourceT m)
• (Apply m) => Apply (ResourceT m)
• (Applicative m) => Applicative (ResourceT m)
• (Bind m) => Bind (ResourceT m)
• (Monad m) => Monad (ResourceT m)
• MonadTrans ResourceT
• (MonadAsk r m) => MonadAsk r (ResourceT m)
• (MonadReader r m) => MonadReader r (ResourceT m)
• (MonadTell w m) => MonadTell w (ResourceT m)
• (MonadWriter w m) => MonadWriter w (ResourceT m)
• (MonadState s m) => MonadState s (ResourceT m)
• (MonadCont m) => MonadCont (ResourceT m)
• (MonadThrow e m) => MonadThrow e (ResourceT m)
• (MonadError e m) => MonadError e (ResourceT m)
• (MonadEffect m) => MonadEffect (ResourceT m)
• (MonadAff m) => MonadAff (ResourceT m)
• (MonadRec m) => MonadRec (ResourceT m)
• (Monad m, Alt m) => Alt (ResourceT m)
• (Monad m, Plus m) => Plus (ResourceT m)
• (Monad m, Alternative m) => Alternative (ResourceT m)
• (MonadPlus m) => MonadPlus (ResourceT m)
• (Parallel f m) => Parallel (ResourceT f) (ResourceT m)

type Resource = ResourceT Aff

The Resource monad is a synonym for ResourceT Aff.

mapResourceT :: forall m m' a b. (m a -> m' b) -> ResourceT m a -> ResourceT m' b

Change the type of the result in a ResourceT monad action.

runResourceT :: forall m a b. (m a -> Aff b) -> ResourceT m a -> Aff b

Run a computation in the ResourceT monad, while changing it to Aff to ensure the cleanup will run safely.

runResource :: forall a. Resource a -> Aff a

Run an Aff computation in the ResourceT monad.

joinResourceT :: forall m a. ResourceT (ResourceT m) a -> ResourceT m a

This function mirrors join at the transformer level: it will collapse two levels of ResourceT into a single ResourceT.