Control.OOP.MonadVar

Documentation

class Monad m => MonadConstVar v m | m -> v where

Generalized read-only access to mutable variables

Minimal complete definition

readVar

Methods

readVar :: v a -> m a

Instances

MonadIO m => MonadConstVar IORef m

Methods

readVar :: IORef a -> m a

class (Monad m, MonadConstVar v m) => MonadVar v m | m -> v where

Generalized mutable variables

Minimal complete definition

newVar, writeVar, transaction

Methods

newVar :: a -> m (v a)

writeVar :: a -> v a -> m ()

modifyVar :: (a -> a) -> v a -> m ()

swapVar :: a -> v a -> m a

modifySwapVar :: (a -> a) -> v a -> m a

transaction :: Proxy v -> m a -> m a

Instances

MonadIO m => MonadVar IORef m

Methods

newVar :: a -> m (IORef a)

writeVar :: a -> IORef a -> m ()

modifyVar :: (a -> a) -> IORef a -> m ()

swapVar :: a -> IORef a -> m a

modifySwapVar :: (a -> a) -> IORef a -> m a

transaction :: Proxy (* -> *) IORef -> m a -> m a