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/Haskell 9

Control.Monad.STM

Copyright (c) The University of Glasgow 2004
License BSD-style (see the file libraries/base/LICENSE)
Maintainer [email protected]
Stability experimental
Portability non-portable (requires STM)
Safe Haskell Trustworthy
Language Haskell2010

Contents

Description

Software Transactional Memory: a modular composable concurrency abstraction. See

This module only defines the STM monad; you probably want to import Control.Concurrent.STM (which exports Control.Monad.STM).

Note that invariant checking (namely the always and alwaysSucceeds functions) has been removed. See ticket #14324 and the removal proposal. Existing users are encouraged to encapsulate their STM operations in safe abstractions which can perform the invariant checking without help from the runtime system.

data STM a

Instances
Instances details
Alternative STM
Instance details

Defined in GHC.Internal.Conc.Sync

Methods

empty :: STM a

(<|>) :: STM a -> STM a -> STM a

some :: STM a -> STM [a]

many :: STM a -> STM [a]

Applicative STM
Instance details

Defined in GHC.Internal.Conc.Sync

Methods

pure :: a -> STM a

(<*>) :: STM (a -> b) -> STM a -> STM b

liftA2 :: (a -> b -> c) -> STM a -> STM b -> STM c

(*>) :: STM a -> STM b -> STM b

(<*) :: STM a -> STM b -> STM a

Functor STM
Instance details

Defined in GHC.Internal.Conc.Sync

Methods

fmap :: (a -> b) -> STM a -> STM b

(<$) :: a -> STM b -> STM a

Monad STM
Instance details

Defined in GHC.Internal.Conc.Sync

Methods

(>>=) :: STM a -> (a -> STM b) -> STM b

(>>) :: STM a -> STM b -> STM b

return :: a -> STM a

MonadPlus STM
Instance details

Defined in GHC.Internal.Conc.Sync

Methods

mzero :: STM a

mplus :: STM a -> STM a -> STM a

MonadFix STM Source

Since: stm-2.3
Instance details

Defined in Control.Monad.STM

Methods

mfix :: (a -> STM a) -> STM a

MArray TArray e STM Source
Instance details

Defined in Control.Concurrent.STM.TArray

Methods

getBounds :: Ix i => TArray i e -> STM (i, i) Source

getNumElements :: Ix i => TArray i e -> STM Int Source

newArray :: Ix i => (i, i) -> e -> STM (TArray i e) Source

newArray_ :: Ix i => (i, i) -> STM (TArray i e) Source

unsafeNewArray_ :: Ix i => (i, i) -> STM (TArray i e) Source

unsafeRead :: Ix i => TArray i e -> Int -> STM e Source

unsafeWrite :: Ix i => TArray i e -> Int -> e -> STM () Source

Monoid a => Monoid (STM a)
Instance details

Defined in GHC.Internal.Conc.Sync

Methods

mempty :: STM a

mappend :: STM a -> STM a -> STM a

mconcat :: [STM a] -> STM a

Semigroup a => Semigroup (STM a)
Instance details

Defined in GHC.Internal.Conc.Sync

Methods

(<>) :: STM a -> STM a -> STM a

sconcat :: NonEmpty (STM a) -> STM a

stimes :: Integral b => b -> STM a -> STM a

atomically :: STM a -> IO a

retry :: STM a

orElse :: STM a -> STM a -> STM a

check :: Bool -> STM () Source

Check that the boolean condition is true and, if not, retry.

In other words, check b = unless b retry.

Since: stm-2.1.1

throwSTM :: Exception e => e -> STM a

catchSTM :: Exception e => STM a -> (e -> STM a) -> STM a

Orphan instances

MonadFix STM Source

Since: stm-2.3
Instance details

Methods

mfix :: (a -> STM a) -> STM a

© The University of Glasgow and others
Licensed under a BSD-style license (see top of the page).
https://downloads.haskell.org/~ghc/9.12.1/docs/libraries/stm-2.5.3.1-9996/Control-Monad-STM.html