Safe Haskell	None
Language	Haskell2010

Control.Effect.State

Contents

Effect
Actions
Interpretations
Simple variants of interpretations
Threading constraints
Carriers

Synopsis

data State s :: Effect where
- Get :: State s m s
- Put :: s -> State s m ()
state :: Eff (State s) m => (s -> (s, a)) -> m a
state' :: Eff (State s) m => (s -> (s, a)) -> m a
get :: Eff (State s) m => m s
gets :: Eff (State s) m => (s -> a) -> m a
put :: Eff (State s) m => s -> m ()
modify :: Eff (State s) m => (s -> s) -> m ()
modify' :: Eff (State s) m => (s -> s) -> m ()
runState :: forall s m a p. (Carrier m, Threaders '[StateThreads] m p) => s -> StateC s m a -> m (s, a)
evalState :: forall s m a p. (Carrier m, Threaders '[StateThreads] m p) => s -> StateC s m a -> m a
execState :: forall s m a p. (Carrier m, Threaders '[StateThreads] m p) => s -> StateC s m a -> m s
runStateLazy :: forall s m a p. (Carrier m, Threaders '[StateLazyThreads] m p) => s -> StateLazyC s m a -> m (s, a)
evalStateLazy :: forall s m a p. (Carrier m, Threaders '[StateLazyThreads] m p) => s -> StateLazyC s m a -> m a
execStateLazy :: forall s m a p. (Carrier m, Threaders '[StateLazyThreads] m p) => s -> StateLazyC s m a -> m s
stateToIO :: forall s m a. Eff (Embed IO) m => s -> InterpretReifiedC (State s) m a -> m (s, a)
runStateIORef :: forall s m a. Eff (Embed IO) m => IORef s -> InterpretReifiedC (State s) m a -> m a
stateToIOSimple :: forall s m a p. (Eff (Embed IO) m, Threaders '[ReaderThreads] m p) => s -> InterpretSimpleC (State s) m a -> m (s, a)
runStateIORefSimple :: forall s m a p. (Eff (Embed IO) m, Threaders '[ReaderThreads] m p) => IORef s -> InterpretSimpleC (State s) m a -> m a
class (forall s. Threads (StateT s) p) => StateThreads p
class (forall s. Threads (StateT s) p) => StateLazyThreads p
data StateC s m a
data StateLazyC s m a

Effect

data State s :: Effect where Source #

An effect for non-atomic stateful operations.

If you need atomicity, use AtomicState instead.

Constructors

Get :: State s m s
Put :: s -> State s m ()

Actions

state :: Eff (State s) m => (s -> (s, a)) -> m a Source #

Read and modify the state.

The resulting tuple of the computation is forced. You can control what parts of the computation are evaluated by tying their evaluation to the tuple.

state' :: Eff (State s) m => (s -> (s, a)) -> m a Source #

A variant of state that forces the resulting state (but not the return value)

get :: Eff (State s) m => m s Source #

gets :: Eff (State s) m => (s -> a) -> m a Source #

put :: Eff (State s) m => s -> m () Source #

modify :: Eff (State s) m => (s -> s) -> m () Source #

modify' :: Eff (State s) m => (s -> s) -> m () Source #

A variant of modify that forces the resulting state.

Interpretations

runState :: forall s m a p. (Carrier m, Threaders '[StateThreads] m p) => s -> StateC s m a -> m (s, a) Source #

Runs a State s effect purely.

Derivs (StateC s m) = State s ': Derivs m

Prims  (StateC e m) = Prims m

evalState :: forall s m a p. (Carrier m, Threaders '[StateThreads] m p) => s -> StateC s m a -> m a Source #

Runs a State s effect purely, discarding the end state.

execState :: forall s m a p. (Carrier m, Threaders '[StateThreads] m p) => s -> StateC s m a -> m s Source #

Runs a State s effect purely, discarding the end result.

runStateLazy :: forall s m a p. (Carrier m, Threaders '[StateLazyThreads] m p) => s -> StateLazyC s m a -> m (s, a) Source #

Runs a State s effect purely and lazily.

Derivs (StateLazyC s m) = State s ': Derivs m

Prims  (StateLazyC e m) = Prims m

evalStateLazy :: forall s m a p. (Carrier m, Threaders '[StateLazyThreads] m p) => s -> StateLazyC s m a -> m a Source #

Runs a State s effect purely and lazily, discarding the final state.

execStateLazy :: forall s m a p. (Carrier m, Threaders '[StateLazyThreads] m p) => s -> StateLazyC s m a -> m s Source #

Runs a State s effect purely and lazily, discarding the end result.

stateToIO :: forall s m a. Eff (Embed IO) m => s -> InterpretReifiedC (State s) m a -> m (s, a) Source #

Runs a State s effect by transforming it into non-atomic operations in IO.

This has a higher-rank type, as it makes use of InterpretReifiedC. This makes stateToIO very difficult to use partially applied. In particular, it can't be composed using ..

If performance is secondary, consider using the slower stateToIOSimple, which doesn't have a higher-rank type.

runStateIORef :: forall s m a. Eff (Embed IO) m => IORef s -> InterpretReifiedC (State s) m a -> m a Source #

Runs a State s effect by transforming it into non-atomic operations over an IORef.

This has a higher-rank type, as it makes use of InterpretReifiedC. This makes runStateIORef very difficult to use partially applied. In particular, it can't be composed using ..

If performance is secondary, consider using the slower runStateIORefSimple, which doesn't have a higher-rank type.

Simple variants of interpretations

stateToIOSimple :: forall s m a p. (Eff (Embed IO) m, Threaders '[ReaderThreads] m p) => s -> InterpretSimpleC (State s) m a -> m (s, a) Source #

Runs a State s effect by transforming it into non-atomic operations in IO.

This is a less performant version of stateToIO that doesn't have a higher-rank type, making it much easier to use partially applied.

runStateIORefSimple :: forall s m a p. (Eff (Embed IO) m, Threaders '[ReaderThreads] m p) => IORef s -> InterpretSimpleC (State s) m a -> m a Source #

Runs a State s effect by transforming it into non-atomic operations over an IORef.

This is a less performant version of runStateIORef that doesn't have a higher-rank type, making it much easier to use partially applied.

Threading constraints

class (forall s. Threads (StateT s) p) => StateThreads p Source #

StateThreads accepts the following primitive effects:

Regional s
Optional s (when s is a functor)
BaseControl b
ListenPrim o (when o is a Monoid)
WriterPrim o (when o is a Monoid)
ReaderPrim i
Mask
Bracket
Fix
Split

Instances

Instances details

(forall s. Threads (StateT s) p) => StateThreads p Source #
Instance details Defined in Control.Effect.Internal.State

class (forall s. Threads (StateT s) p) => StateLazyThreads p Source #

StateLazyThreads accepts the following primitive effects:

Regional s
Optional s (when s is a functor)
BaseControl b
ListenPrim o (when o is a Monoid)
WriterPrim o (when o is a Monoid)
ReaderPrim i
Mask
Bracket
Fix
Split

Instances

Instances details

(forall s. Threads (StateT s) p) => StateLazyThreads p Source #
Instance details Defined in Control.Effect.Internal.State

Carriers

data StateC s m a Source #

Instances

Instances details

MonadBase b m => MonadBase b (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods liftBase :: b α -> StateC s m α #
MonadBaseControl b m => MonadBaseControl b (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Associated Types type StM (StateC s m) a # Methods liftBaseWith :: (RunInBase (StateC s m) b -> b a) -> StateC s m a # restoreM :: StM (StateC s m) a -> StateC s m a #
MonadTrans (StateC s) Source #
Instance details Defined in Control.Effect.Internal.State Methods lift :: Monad m => m a -> StateC s m a #
MonadTransControl (StateC s) Source #
Instance details Defined in Control.Effect.Internal.State Associated Types type StT (StateC s) a # Methods liftWith :: Monad m => (Run (StateC s) -> m a) -> StateC s m a # restoreT :: Monad m => m (StT (StateC s) a) -> StateC s m a #
Monad m => Monad (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods (>>=) :: StateC s m a -> (a -> StateC s m b) -> StateC s m b # (>>) :: StateC s m a -> StateC s m b -> StateC s m b # return :: a -> StateC s m a #
Functor m => Functor (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods fmap :: (a -> b) -> StateC s m a -> StateC s m b # (<$) :: a -> StateC s m b -> StateC s m a #
MonadFix m => MonadFix (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods mfix :: (a -> StateC s m a) -> StateC s m a #
MonadFail m => MonadFail (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods fail :: String -> StateC s m a #
Monad m => Applicative (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods pure :: a -> StateC s m a # (<>) :: StateC s m (a -> b) -> StateC s m a -> StateC s m b # liftA2 :: (a -> b -> c) -> StateC s m a -> StateC s m b -> StateC s m c # (>) :: StateC s m a -> StateC s m b -> StateC s m b # (<*) :: StateC s m a -> StateC s m b -> StateC s m a #
MonadIO m => MonadIO (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods liftIO :: IO a -> StateC s m a #
MonadPlus m => Alternative (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods empty :: StateC s m a # (<\|>) :: StateC s m a -> StateC s m a -> StateC s m a # some :: StateC s m a -> StateC s m [a] # many :: StateC s m a -> StateC s m [a] #
MonadPlus m => MonadPlus (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods mzero :: StateC s m a # mplus :: StateC s m a -> StateC s m a -> StateC s m a #
MonadThrow m => MonadThrow (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods throwM :: Exception e => e -> StateC s m a #
MonadCatch m => MonadCatch (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods catch :: Exception e => StateC s m a -> (e -> StateC s m a) -> StateC s m a #
MonadMask m => MonadMask (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods mask :: ((forall a. StateC s m a -> StateC s m a) -> StateC s m b) -> StateC s m b # uninterruptibleMask :: ((forall a. StateC s m a -> StateC s m a) -> StateC s m b) -> StateC s m b # generalBracket :: StateC s m a -> (a -> ExitCase b -> StateC s m c) -> (a -> StateC s m b) -> StateC s m (b, c) #
(Carrier m, Threads (StateT s) (Prims m)) => Carrier (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State Associated Types type Derivs (StateC s m) :: [Effect] Source # type Prims (StateC s m) :: [Effect] Source # Methods algPrims :: Algebra' (Prims (StateC s m)) (StateC s m) a Source # reformulate :: Monad z => Reformulation' (Derivs (StateC s m)) (Prims (StateC s m)) (StateC s m) z a Source # algDerivs :: Algebra' (Derivs (StateC s m)) (StateC s m) a Source #
type StT (StateC s) a Source #
Instance details Defined in Control.Effect.Internal.State type StT (StateC s) a = StT (StateT s) a
type Derivs (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State type Derivs (StateC s m) = State s ': Derivs m
type Prims (StateC s m) Source #
Instance details Defined in Control.Effect.Internal.State type Prims (StateC s m) = Prims m
type StM (StateC s m) a Source #
Instance details Defined in Control.Effect.Internal.State type StM (StateC s m) a = StM (StateT s m) a

data StateLazyC s m a Source #

Instances

Instances details

MonadBase b m => MonadBase b (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods liftBase :: b α -> StateLazyC s m α #
MonadBaseControl b m => MonadBaseControl b (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Associated Types type StM (StateLazyC s m) a # Methods liftBaseWith :: (RunInBase (StateLazyC s m) b -> b a) -> StateLazyC s m a # restoreM :: StM (StateLazyC s m) a -> StateLazyC s m a #
MonadTrans (StateLazyC s) Source #
Instance details Defined in Control.Effect.Internal.State Methods lift :: Monad m => m a -> StateLazyC s m a #
MonadTransControl (StateLazyC s) Source #
Instance details Defined in Control.Effect.Internal.State Associated Types type StT (StateLazyC s) a # Methods liftWith :: Monad m => (Run (StateLazyC s) -> m a) -> StateLazyC s m a # restoreT :: Monad m => m (StT (StateLazyC s) a) -> StateLazyC s m a #
Monad m => Monad (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods (>>=) :: StateLazyC s m a -> (a -> StateLazyC s m b) -> StateLazyC s m b # (>>) :: StateLazyC s m a -> StateLazyC s m b -> StateLazyC s m b # return :: a -> StateLazyC s m a #
Functor m => Functor (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods fmap :: (a -> b) -> StateLazyC s m a -> StateLazyC s m b # (<$) :: a -> StateLazyC s m b -> StateLazyC s m a #
MonadFix m => MonadFix (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods mfix :: (a -> StateLazyC s m a) -> StateLazyC s m a #
MonadFail m => MonadFail (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods fail :: String -> StateLazyC s m a #
Monad m => Applicative (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods pure :: a -> StateLazyC s m a # (<>) :: StateLazyC s m (a -> b) -> StateLazyC s m a -> StateLazyC s m b # liftA2 :: (a -> b -> c) -> StateLazyC s m a -> StateLazyC s m b -> StateLazyC s m c # (>) :: StateLazyC s m a -> StateLazyC s m b -> StateLazyC s m b # (<*) :: StateLazyC s m a -> StateLazyC s m b -> StateLazyC s m a #
MonadIO m => MonadIO (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods liftIO :: IO a -> StateLazyC s m a #
MonadPlus m => Alternative (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods empty :: StateLazyC s m a # (<\|>) :: StateLazyC s m a -> StateLazyC s m a -> StateLazyC s m a # some :: StateLazyC s m a -> StateLazyC s m [a] # many :: StateLazyC s m a -> StateLazyC s m [a] #
MonadPlus m => MonadPlus (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods mzero :: StateLazyC s m a # mplus :: StateLazyC s m a -> StateLazyC s m a -> StateLazyC s m a #
MonadThrow m => MonadThrow (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods throwM :: Exception e => e -> StateLazyC s m a #
MonadCatch m => MonadCatch (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods catch :: Exception e => StateLazyC s m a -> (e -> StateLazyC s m a) -> StateLazyC s m a #
MonadMask m => MonadMask (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Methods mask :: ((forall a. StateLazyC s m a -> StateLazyC s m a) -> StateLazyC s m b) -> StateLazyC s m b # uninterruptibleMask :: ((forall a. StateLazyC s m a -> StateLazyC s m a) -> StateLazyC s m b) -> StateLazyC s m b # generalBracket :: StateLazyC s m a -> (a -> ExitCase b -> StateLazyC s m c) -> (a -> StateLazyC s m b) -> StateLazyC s m (b, c) #
(Carrier m, Threads (StateT s) (Prims m)) => Carrier (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State Associated Types type Derivs (StateLazyC s m) :: [Effect] Source # type Prims (StateLazyC s m) :: [Effect] Source # Methods algPrims :: Algebra' (Prims (StateLazyC s m)) (StateLazyC s m) a Source # reformulate :: Monad z => Reformulation' (Derivs (StateLazyC s m)) (Prims (StateLazyC s m)) (StateLazyC s m) z a Source # algDerivs :: Algebra' (Derivs (StateLazyC s m)) (StateLazyC s m) a Source #
type StT (StateLazyC s) a Source #
Instance details Defined in Control.Effect.Internal.State type StT (StateLazyC s) a = StT (StateT s) a
type Derivs (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State type Derivs (StateLazyC s m) = State s ': Derivs m
type Prims (StateLazyC s m) Source #
Instance details Defined in Control.Effect.Internal.State type Prims (StateLazyC s m) = Prims m
type StM (StateLazyC s m) a Source #
Instance details Defined in Control.Effect.Internal.State type StM (StateLazyC s m) a = StM (StateT s m) a