Safe Haskell	None
Language	GHC2021

Effects.Concurrent.STM

Contents

Effect
TVar
TBQueue
Reexports

Description

Provides classes for STM.

Since: 0.1

Synopsis

data STM a
class Monad m => MonadSTM (m :: Type -> Type) where
- atomically :: HasCallStack => STM a -> m a
data TVar a
newTVarA :: (HasCallStack, MonadSTM m) => a -> m (TVar a)
readTVarA :: (HasCallStack, MonadSTM m) => TVar a -> m a
writeTVarA :: (HasCallStack, MonadSTM m) => TVar a -> a -> m ()
modifyTVarA' :: (HasCallStack, MonadSTM m) => TVar a -> (a -> a) -> m ()
data TBQueue a
newTBQueueA :: (HasCallStack, MonadSTM m) => Natural -> m (TBQueue a)
readTBQueueA :: (HasCallStack, MonadSTM m) => TBQueue a -> m a
tryReadTBQueueA :: (HasCallStack, MonadSTM m) => TBQueue a -> m (Maybe a)
writeTBQueueA :: (HasCallStack, MonadSTM m) => TBQueue a -> a -> m ()
flushTBQueueA :: (HasCallStack, MonadSTM m) => TBQueue a -> m [a]
data Natural

Effect

data STM a #

A monad supporting atomic memory transactions.

Instances

Instances details

Alternative STM	Takes the first non-`retry`ing `STM` action. Since: base-4.8.0.0
Instance details Defined in GHC.Conc.Sync Methods empty :: STM a # (<\|>) :: STM a -> STM a -> STM a # some :: STM a -> STM [a] # many :: STM a -> STM [a] #
Applicative STM	Since: base-4.8.0.0
Instance details Defined in GHC.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	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods fmap :: (a -> b) -> STM a -> STM b # (<$) :: a -> STM b -> STM a #
Monad STM	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods (>>=) :: STM a -> (a -> STM b) -> STM b # (>>) :: STM a -> STM b -> STM b # return :: a -> STM a #
MonadPlus STM	Takes the first non-`retry`ing `STM` action. Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods mzero :: STM a # mplus :: STM a -> STM a -> STM a #
MArray TArray e STM
Instance details Defined in Control.Concurrent.STM.TArray Methods getBounds :: Ix i => TArray i e -> STM (i, i) # getNumElements :: Ix i => TArray i e -> STM Int # newArray :: Ix i => (i, i) -> e -> STM (TArray i e) # newArray_ :: Ix i => (i, i) -> STM (TArray i e) # unsafeNewArray_ :: Ix i => (i, i) -> STM (TArray i e) # unsafeRead :: Ix i => TArray i e -> Int -> STM e # unsafeWrite :: Ix i => TArray i e -> Int -> e -> STM () #
Monoid a => Monoid (STM a)	Since: base-4.17.0.0
Instance details Defined in GHC.Conc.Sync Methods mempty :: STM a # mappend :: STM a -> STM a -> STM a # mconcat :: [STM a] -> STM a #
Semigroup a => Semigroup (STM a)	Since: base-4.17.0.0
Instance details Defined in GHC.Conc.Sync Methods (<>) :: STM a -> STM a -> STM a # sconcat :: NonEmpty (STM a) -> STM a # stimes :: Integral b => b -> STM a -> STM a #

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

STM effect. Note that this class is for monads that can lift entire STM transactions (i.e. atomically). It is not intended for "STM-like" monads -- hence has no STM instance -- as the semantics for "STM-like" and "can lift STM atomically" are different.

Since: 0.1

Methods

atomically :: HasCallStack => STM a -> m a Source #

Lifted atomically.

Since: 0.1

Instances

Instances details

MonadSTM IO Source #	Since: 0.1
Instance details Defined in Effects.Concurrent.STM Methods atomically :: HasCallStack => STM a -> IO a Source #
MonadSTM m => MonadSTM (ReaderT e m) Source #	Since: 0.1
Instance details Defined in Effects.Concurrent.STM Methods atomically :: HasCallStack => STM a -> ReaderT e m a Source #

TVar

data TVar a #

Shared memory locations that support atomic memory transactions.

Instances

Instances details

Eq (TVar a)	Since: base-4.8.0.0
Instance details Defined in GHC.Conc.Sync Methods (==) :: TVar a -> TVar a -> Bool # (/=) :: TVar a -> TVar a -> Bool #

newTVarA :: (HasCallStack, MonadSTM m) => a -> m (TVar a) Source #

Create a new TVar holding a value supplied and lifts the result via atomically.

Since: 0.1

readTVarA :: (HasCallStack, MonadSTM m) => TVar a -> m a Source #

Return the current value stored in a TVar and lifts the result via atomically.

Since: 0.1

writeTVarA :: (HasCallStack, MonadSTM m) => TVar a -> a -> m () Source #

Write the supplied value into a TVar and lifts the action via atomically.

Since: 0.1

modifyTVarA' :: (HasCallStack, MonadSTM m) => TVar a -> (a -> a) -> m () Source #

Strict version of modifyTVar, lifting the action via atomically.

Since: 0.1

TBQueue

data TBQueue a #

TBQueue is an abstract type representing a bounded FIFO channel.

Since: stm-2.4

Instances

Instances details

Eq (TBQueue a)
Instance details Defined in Control.Concurrent.STM.TBQueue Methods (==) :: TBQueue a -> TBQueue a -> Bool # (/=) :: TBQueue a -> TBQueue a -> Bool #

newTBQueueA Source #

Arguments

:: (HasCallStack, MonadSTM m)
=> Natural	maximum number of elements the queue can hold
-> m (TBQueue a)

Builds and returns a new instance of TBQueue, lifting via atomically.

Since: 0.1

readTBQueueA :: (HasCallStack, MonadSTM m) => TBQueue a -> m a Source #

Read the next value from the TBQueue, lifting via atomically.

Since: 0.1

tryReadTBQueueA :: (HasCallStack, MonadSTM m) => TBQueue a -> m (Maybe a) Source #

A version of readTBQueue which does not retry. Instead it returns Nothing if no value is available. Lifts via atomically.

Since: 0.1

writeTBQueueA :: (HasCallStack, MonadSTM m) => TBQueue a -> a -> m () Source #

Write a value to a TBQueue; blocks if the queue is full. Lifts via atomically.

Since: 0.1

flushTBQueueA :: (HasCallStack, MonadSTM m) => TBQueue a -> m [a] Source #

Efficiently read the entire contents of a TBQueue into a list. This function never retries. Lifts via atomically.

Since: 0.1

Reexports

data Natural #

Natural number

Invariant: numbers <= 0xffffffffffffffff use the NS constructor

Instances

Instances details

Data Natural	Since: base-4.8.0.0
Instance details Defined in Data.Data Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Natural -> c Natural # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Natural # toConstr :: Natural -> Constr # dataTypeOf :: Natural -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Natural) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Natural) # gmapT :: (forall b. Data b => b -> b) -> Natural -> Natural # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Natural -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Natural -> r # gmapQ :: (forall d. Data d => d -> u) -> Natural -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Natural -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Natural -> m Natural # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Natural -> m Natural # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Natural -> m Natural #
Bits Natural	Since: base-4.8.0
Instance details Defined in GHC.Bits Methods (.&.) :: Natural -> Natural -> Natural # (.\|.) :: Natural -> Natural -> Natural # xor :: Natural -> Natural -> Natural # complement :: Natural -> Natural # shift :: Natural -> Int -> Natural # rotate :: Natural -> Int -> Natural # zeroBits :: Natural # bit :: Int -> Natural # setBit :: Natural -> Int -> Natural # clearBit :: Natural -> Int -> Natural # complementBit :: Natural -> Int -> Natural # testBit :: Natural -> Int -> Bool # bitSizeMaybe :: Natural -> Maybe Int # bitSize :: Natural -> Int # isSigned :: Natural -> Bool # shiftL :: Natural -> Int -> Natural # unsafeShiftL :: Natural -> Int -> Natural # shiftR :: Natural -> Int -> Natural # unsafeShiftR :: Natural -> Int -> Natural # rotateL :: Natural -> Int -> Natural # rotateR :: Natural -> Int -> Natural # popCount :: Natural -> Int #
Enum Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Enum Methods succ :: Natural -> Natural # pred :: Natural -> Natural # toEnum :: Int -> Natural # fromEnum :: Natural -> Int # enumFrom :: Natural -> [Natural] # enumFromThen :: Natural -> Natural -> [Natural] # enumFromTo :: Natural -> Natural -> [Natural] # enumFromThenTo :: Natural -> Natural -> Natural -> [Natural] #
Ix Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Ix Methods range :: (Natural, Natural) -> [Natural] # index :: (Natural, Natural) -> Natural -> Int # unsafeIndex :: (Natural, Natural) -> Natural -> Int # inRange :: (Natural, Natural) -> Natural -> Bool # rangeSize :: (Natural, Natural) -> Int # unsafeRangeSize :: (Natural, Natural) -> Int #
Num Natural	Note that `Natural`'s `Num` instance isn't a ring: no element but 0 has an additive inverse. It is a semiring though. Since: base-4.8.0.0
Instance details Defined in GHC.Num Methods (+) :: Natural -> Natural -> Natural # (-) :: Natural -> Natural -> Natural # (*) :: Natural -> Natural -> Natural # negate :: Natural -> Natural # abs :: Natural -> Natural # signum :: Natural -> Natural # fromInteger :: Integer -> Natural #
Read Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Natural # readList :: ReadS [Natural] # readPrec :: ReadPrec Natural # readListPrec :: ReadPrec [Natural] #
Integral Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Real Methods quot :: Natural -> Natural -> Natural # rem :: Natural -> Natural -> Natural # div :: Natural -> Natural -> Natural # mod :: Natural -> Natural -> Natural # quotRem :: Natural -> Natural -> (Natural, Natural) # divMod :: Natural -> Natural -> (Natural, Natural) # toInteger :: Natural -> Integer #
Real Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Real Methods toRational :: Natural -> Rational #
Show Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Natural -> ShowS # show :: Natural -> String # showList :: [Natural] -> ShowS #
PrintfArg Natural	Since: base-4.8.0.0
Instance details Defined in Text.Printf Methods formatArg :: Natural -> FieldFormatter # parseFormat :: Natural -> ModifierParser #
Eq Natural
Instance details Defined in GHC.Num.Natural Methods (==) :: Natural -> Natural -> Bool # (/=) :: Natural -> Natural -> Bool #
Ord Natural
Instance details Defined in GHC.Num.Natural Methods compare :: Natural -> Natural -> Ordering # (<) :: Natural -> Natural -> Bool # (<=) :: Natural -> Natural -> Bool # (>) :: Natural -> Natural -> Bool # (>=) :: Natural -> Natural -> Bool # max :: Natural -> Natural -> Natural # min :: Natural -> Natural -> Natural #
KnownNat n => HasResolution (n :: Nat)	For example, `Fixed 1000` will give you a `Fixed` with a resolution of 1000.
Instance details Defined in Data.Fixed Methods resolution :: p n -> Integer #
TestCoercion SNat	Since: base-4.18.0.0
Instance details Defined in GHC.TypeNats Methods testCoercion :: forall (a :: Nat) (b :: Nat). SNat a -> SNat b -> Maybe (Coercion a b) #
TestEquality SNat	Since: base-4.18.0.0
Instance details Defined in GHC.TypeNats Methods testEquality :: forall (a :: Nat) (b :: Nat). SNat a -> SNat b -> Maybe (a :~: b) #
type Compare (a :: Natural) (b :: Natural)
Instance details Defined in Data.Type.Ord type Compare (a :: Natural) (b :: Natural) = CmpNat a b