Safe Haskell	None
Language	GHC2021

Multitasking.MonadSTM

Synopsis

class Monad m => MonadSTM (m :: Type -> Type) where
- liftSTM :: STM a -> m a
- liftSTM_IO :: STM a -> IO a -> m a

Documentation

class Monad m => MonadSTM (m :: Type -> Type) where Source #

MonadSTM is a class for all monads which can do STM actions.

Keep in mind that while some monads (e.g. IO) can do STM, your STM actions may not be executed atomically if you run them all in the IO monad. Keep them together in STM and then use one liftSTM to lift them to the IO monad.

Minimal complete definition

liftSTM

Methods

liftSTM :: STM a -> m a Source #

Lift STM into the monad m.

Keep in mind that liftSTM may lose atomicity. `liftSTM action1 >> liftSTM action2` might not be atomic, depending on the monad m. Use `liftSTM (action1 >> action2)` instead.

liftSTM_IO :: STM a -> IO a -> m a Source #

Lift an action which can be done in STM or in IO. This can be useful if the IO version is more performant.

Instances

Instances details

MonadSTM STM Source #
Instance details Defined in Multitasking.MonadSTM Methods liftSTM :: STM a -> STM a Source # liftSTM_IO :: STM a -> IO a -> STM a Source #
MonadSTM IO Source #
Instance details Defined in Multitasking.MonadSTM Methods liftSTM :: STM a -> IO a Source # liftSTM_IO :: STM a -> IO a -> IO a Source #
(MonadSTM m, MonadTrans t) => MonadSTM (t m) Source #
Instance details Defined in Multitasking.MonadSTM Methods liftSTM :: STM a -> t m a Source # liftSTM_IO :: STM a -> IO a -> t m a Source #