Copyright	Liyang HU Bas van Dijk
License	BSD-style
Maintainer	Bas van Dijk <v.dijk.bas@gmail.com>
Stability	experimental
Safe Haskell	Safe
Language	Haskell98

Data.IORef.Lifted

Description

This is a wrapped version of Data.IORef with types generalised from IO to all monads in MonadBase.

Synopsis

data IORef a
newIORef :: MonadBase IO m => a -> m (IORef a)
readIORef :: MonadBase IO m => IORef a -> m a
writeIORef :: MonadBase IO m => IORef a -> a -> m ()
modifyIORef :: MonadBase IO m => IORef a -> (a -> a) -> m ()
modifyIORef' :: MonadBase IO m => IORef a -> (a -> a) -> m ()
atomicModifyIORef :: MonadBase IO m => IORef a -> (a -> (a, b)) -> m b
atomicModifyIORef' :: MonadBase IO m => IORef a -> (a -> (a, b)) -> m b
atomicWriteIORef :: MonadBase IO m => IORef a -> a -> m ()
mkWeakIORef :: MonadBaseControl IO m => IORef a -> m () -> m (Weak (IORef a))

Documentation

data IORef a #

A mutable variable in the IO monad.

>>> import Data.IORef
>>> r <- newIORef 0
>>> readIORef r
0
>>> writeIORef r 1
>>> readIORef r
1
>>> atomicWriteIORef r 2
>>> readIORef r
2
>>> modifyIORef' r (+ 1)
>>> readIORef r
3
>>> atomicModifyIORef' r (\a -> (a + 1, ()))
>>> readIORef r
4

Instances

Instances details

Eq (IORef a)

Pointer equality.

Since: base-4.0.0.0

Instance details

Defined in GHC.IORef

Methods

(==) :: IORef a -> IORef a -> Bool #

(/=) :: IORef a -> IORef a -> Bool #

newIORef :: MonadBase IO m => a -> m (IORef a) Source #

Generalized version of newIORef.

readIORef :: MonadBase IO m => IORef a -> m a Source #

Generalized version of readIORef.

writeIORef :: MonadBase IO m => IORef a -> a -> m () Source #

Generalized version of writeIORef.

modifyIORef :: MonadBase IO m => IORef a -> (a -> a) -> m () Source #

Generalized version of modifyIORef.

modifyIORef' :: MonadBase IO m => IORef a -> (a -> a) -> m () Source #

Generalized version of modifyIORef'.

atomicModifyIORef :: MonadBase IO m => IORef a -> (a -> (a, b)) -> m b Source #

Generalized version of atomicModifyIORef.

atomicModifyIORef' :: MonadBase IO m => IORef a -> (a -> (a, b)) -> m b Source #

Generalized version of atomicModifyIORef'.

atomicWriteIORef :: MonadBase IO m => IORef a -> a -> m () Source #

Generalized version of atomicWriteIORef.

mkWeakIORef :: MonadBaseControl IO m => IORef a -> m () -> m (Weak (IORef a)) Source #

Generalized version of mkWeakIORef.

Note any monadic side effects in m of the "finalizer" computation are discarded.