Polysemy.AtomicState

Effect

data AtomicState s m a where

Constructors

AtomicState :: (s -> (s, a)) -> AtomicState s m a

AtomicGet :: AtomicState s m s

Instances

type DefiningModule (AtomicState :: Type -> k -> Type -> Type)

Defined in Polysemy.AtomicState

type DefiningModule (AtomicState :: Type -> k -> Type -> Type) = "Polysemy.AtomicState"

Actions

atomicState :: forall s a r. Member (AtomicState s) r => (s -> (s, a)) -> Sem r a

Atomically reads and modifies the state.

atomicState' :: Member (AtomicState s) r => (s -> (s, a)) -> Sem r a

A variant of atomicState in which the computation is strict in the new state and return value.

atomicGet :: forall s r. Member (AtomicState s) r => Sem r s

atomicPut :: Member (AtomicState s) r => s -> Sem r ()

atomicModify :: Member (AtomicState s) r => (s -> s) -> Sem r ()

atomicModify' :: Member (AtomicState s) r => (s -> s) -> Sem r ()

A variant of atomicModify in which the computation is strict in the new state.

Interpretations

runAtomicStateIORef :: Member (Embed IO) r => IORef s -> Sem (AtomicState s ': r) a -> Sem r a

Run an AtomicState effect by transforming it into atomic operations over an IORef.

runAtomicStateTVar :: Member (Embed IO) r => TVar s -> Sem (AtomicState s ': r) a -> Sem r a

Run an AtomicState effect by transforming it into atomic operations over a TVar.

atomicStateToState :: Member (State s) r => Sem (AtomicState s ': r) a -> Sem r a

Transform an AtomicState effect to a State effect, discarding the notion of atomicity.