Safe Haskell	Safe-Inferred
Language	Haskell2010

Effectful.State.Dynamic

Contents

Description

The dynamically dispatched variant of the State effect.

Note: unless you plan to change interpretations at runtime, it's recommended to use one of the statically dispatched variants, i.e. Effectful.State.Static.Local or Effectful.State.Static.Shared.

Synopsis

data State s :: Effect where
- Get :: State s m s
- Put :: s -> State s m ()
- State :: (s -> (a, s)) -> State s m a
- StateM :: (s -> m (a, s)) -> State s m a
runStateLocal :: s -> Eff (State s ': es) a -> Eff es (a, s)
evalStateLocal :: s -> Eff (State s ': es) a -> Eff es a
execStateLocal :: s -> Eff (State s ': es) a -> Eff es s
runStateShared :: s -> Eff (State s ': es) a -> Eff es (a, s)
evalStateShared :: s -> Eff (State s ': es) a -> Eff es a
execStateShared :: s -> Eff (State s ': es) a -> Eff es s
get :: (HasCallStack, State s :> es) => Eff es s
gets :: (HasCallStack, State s :> es) => (s -> a) -> Eff es a
put :: (HasCallStack, State s :> es) => s -> Eff es ()
state :: (HasCallStack, State s :> es) => (s -> (a, s)) -> Eff es a
modify :: (HasCallStack, State s :> es) => (s -> s) -> Eff es ()
stateM :: (HasCallStack, State s :> es) => (s -> Eff es (a, s)) -> Eff es a
modifyM :: (HasCallStack, State s :> es) => (s -> Eff es s) -> Eff es ()

Effect

data State s :: Effect where Source #

Provide access to a mutable value of type s.

Constructors

Instances details

type DispatchOf (State s) Source #
Instance details Defined in Effectful.State.Dynamic type DispatchOf (State s) = 'Dynamic

Handlers

runStateLocal :: s -> Eff (State s ': es) a -> Eff es (a, s) Source #

Run the State effect with the given initial state and return the final value along with the final state (via Effectful.State.Static.Local).

evalStateLocal :: s -> Eff (State s ': es) a -> Eff es a Source #

Run the State effect with the given initial state and return the final value, discarding the final state (via Effectful.State.Static.Local).

execStateLocal :: s -> Eff (State s ': es) a -> Eff es s Source #

Run the State effect with the given initial state and return the final state, discarding the final value (via Effectful.State.Static.Local).

runStateShared :: s -> Eff (State s ': es) a -> Eff es (a, s) Source #

Run the State effect with the given initial state and return the final value along with the final state (via Effectful.State.Static.Shared).

Run the State effect with the given initial state and return the final value, discarding the final state (via Effectful.State.Static.Shared).

Run the State effect with the given initial state and return the final state, discarding the final value (via Effectful.State.Static.Shared).

Fetch the current value of the state.

gets :: (HasCallStack, State s :> es) => (s -> a) -> Eff es a Source #

Get a function of the current state.

gets f ≡ f <$> get

Set the current state to the given value.

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

Apply the function to the current state and return a value.

modify :: (HasCallStack, State s :> es) => (s -> s) -> Eff es () Source #

Apply the function to the current state.

modify f ≡ state (\s -> ((), f s))

stateM :: (HasCallStack, State s :> es) => (s -> Eff es (a, s)) -> Eff es a Source #

Apply the monadic function to the current state and return a value.

modifyM :: (HasCallStack, State s :> es) => (s -> Eff es s) -> Eff es () Source #

Apply the monadic function to the current state.

modifyM f ≡ stateM (\s -> ((), ) <$> f s)