Control.Effect.Reader

Reader effect

data Reader r m k

Constructors

Ask (r -> m k)

forall b. Local (r -> r) (m b) (b -> m k)

Instances

Effect (Reader r)

Defined in Control.Effect.Reader

Methods

handle :: (Functor f, Monad m) => f () -> (forall x. f (m x) -> n (f x)) -> Reader r m a -> Reader r n (f a)

HFunctor (Reader r)

Defined in Control.Effect.Reader

Methods

fmap' :: forall (f :: Type -> Type) a b. Functor (Reader r f) => (a -> b) -> Reader r f a -> Reader r f b

hmap :: Functor m => (forall x. m x -> n x) -> Reader r m a -> Reader r n a

Functor m => Functor (Reader r m)

Defined in Control.Effect.Reader

Methods

fmap :: (a -> b) -> Reader r m a -> Reader r m b

(<$) :: a -> Reader r m b -> Reader r m a

Carrier sig m => Carrier (Reader r :+: sig) (ReaderC r m)

Defined in Control.Effect.Reader

Methods

eff :: (Reader r :+: sig) (ReaderC r m) a -> ReaderC r m a

ask :: (Member (Reader r) sig, Carrier sig m) => m r

Retrieve the environment value.

run (runReader a ask) === a

asks :: (Member (Reader r) sig, Carrier sig m) => (r -> a) -> m a

Project a function out of the current environment value.

snd (run (runReader a (asks (applyFun f)))) === applyFun f a

local :: (Member (Reader r) sig, Carrier sig m) => (r -> r) -> m a -> m a

Run a computation with an environment value locally modified by the passed function.

run (runReader a (local (applyFun f) ask)) === applyFun f a

run (runReader a ((,,) <$> ask <*> local (applyFun f) ask <*> ask)) === (a, applyFun f a, a)

Reader carrier

runReader :: r -> ReaderC r m a -> m a

Run a Reader effect with the passed environment value.

run (runReader a (pure b)) === b

newtype ReaderC r m a

Constructors

ReaderC

Fields

• runReaderC :: r -> m a

Instances

MonadTrans (ReaderC r)

Defined in Control.Effect.Reader

Methods

lift :: Monad m => m a -> ReaderC r m a

Monad m => Monad (ReaderC r m)

Defined in Control.Effect.Reader

Methods

(>>=) :: ReaderC r m a -> (a -> ReaderC r m b) -> ReaderC r m b

(>>) :: ReaderC r m a -> ReaderC r m b -> ReaderC r m b

return :: a -> ReaderC r m a

Functor m => Functor (ReaderC r m)

Defined in Control.Effect.Reader

Methods

fmap :: (a -> b) -> ReaderC r m a -> ReaderC r m b

(<$) :: a -> ReaderC r m b -> ReaderC r m a

MonadFix m => MonadFix (ReaderC s m)

Defined in Control.Effect.Reader

Methods

mfix :: (a -> ReaderC s m a) -> ReaderC s m a

MonadFail m => MonadFail (ReaderC r m)

Defined in Control.Effect.Reader

Methods

fail :: String -> ReaderC r m a

Applicative m => Applicative (ReaderC r m)

Defined in Control.Effect.Reader

Methods

pure :: a -> ReaderC r m a

(<*>) :: ReaderC r m (a -> b) -> ReaderC r m a -> ReaderC r m b

liftA2 :: (a -> b -> c) -> ReaderC r m a -> ReaderC r m b -> ReaderC r m c

(*>) :: ReaderC r m a -> ReaderC r m b -> ReaderC r m b

(<*) :: ReaderC r m a -> ReaderC r m b -> ReaderC r m a

MonadIO m => MonadIO (ReaderC r m)

Defined in Control.Effect.Reader

Methods

liftIO :: IO a -> ReaderC r m a

Alternative m => Alternative (ReaderC r m)

Defined in Control.Effect.Reader

Methods

empty :: ReaderC r m a

(<|>) :: ReaderC r m a -> ReaderC r m a -> ReaderC r m a

some :: ReaderC r m a -> ReaderC r m [a]

many :: ReaderC r m a -> ReaderC r m [a]

(Alternative m, Monad m) => MonadPlus (ReaderC r m)

Defined in Control.Effect.Reader

Methods

mzero :: ReaderC r m a

mplus :: ReaderC r m a -> ReaderC r m a -> ReaderC r m a

MonadUnliftIO m => MonadUnliftIO (ReaderC r m)

Defined in Control.Effect.Reader

Methods

askUnliftIO :: ReaderC r m (UnliftIO (ReaderC r m))

withRunInIO :: ((forall a. ReaderC r m a -> IO a) -> IO b) -> ReaderC r m b

Carrier sig m => Carrier (Reader r :+: sig) (ReaderC r m)

Defined in Control.Effect.Reader

Methods

eff :: (Reader r :+: sig) (ReaderC r m) a -> ReaderC r m a

Re-exports

class (HFunctor sig, Monad m) => Carrier sig m | m -> sig

The class of carriers (results) for algebras (effect handlers) over signatures (effects), whose actions are given by the eff method.

Minimal complete definition

eff

Instances

Carrier Pure PureC

Defined in Control.Effect.Carrier

Methods

eff :: Pure PureC a -> PureC a

(HFunctor eff, Carrier sig m, Member eff sig) => Carrier sig (InterposeC eff m)

Defined in Control.Effect.Interpose

Methods

eff :: sig (InterposeC eff m) a -> InterposeC eff m a

Monad m => Carrier (Lift m) (LiftC m)

Defined in Control.Effect.Lift

Methods

eff :: Lift m (LiftC m) a -> LiftC m a

(Carrier sig m, MonadIO m) => Carrier (Resource :+: sig) (ResourceC m)

Defined in Control.Effect.Resource

Methods

eff :: (Resource :+: sig) (ResourceC m) a -> ResourceC m a

(Carrier sig m, Effect sig) => Carrier (NonDet :+: sig) (NonDetC m)

Defined in Control.Effect.NonDet

Methods

eff :: (NonDet :+: sig) (NonDetC m) a -> NonDetC m a

(Carrier sig m, Effect sig) => Carrier (NonDet :+: sig) (OnceC m)

Defined in Control.Effect.Cull

Methods

eff :: (NonDet :+: sig) (OnceC m) a -> OnceC m a

(Carrier sig m, Effect sig) => Carrier (Fresh :+: sig) (FreshC m)

Defined in Control.Effect.Fresh

Methods

eff :: (Fresh :+: sig) (FreshC m) a -> FreshC m a

(Carrier sig m, Effect sig) => Carrier (Fail :+: sig) (FailC m)

Defined in Control.Effect.Fail

Methods

eff :: (Fail :+: sig) (FailC m) a -> FailC m a

(Carrier sig m, Effect sig) => Carrier (Cut :+: (NonDet :+: sig)) (CutC m)

Defined in Control.Effect.Cut

Methods

eff :: (Cut :+: (NonDet :+: sig)) (CutC m) a -> CutC m a

(Carrier sig m, Effect sig) => Carrier (Cull :+: (NonDet :+: sig)) (CullC m)

Defined in Control.Effect.Cull

Methods

eff :: (Cull :+: (NonDet :+: sig)) (CullC m) a -> CullC m a

(Carrier sig m, Effect sig) => Carrier (Trace :+: sig) (TraceByReturningC m)

Defined in Control.Effect.Trace

Methods

eff :: (Trace :+: sig) (TraceByReturningC m) a -> TraceByReturningC m a

Carrier sig m => Carrier (Trace :+: sig) (TraceByIgnoringC m)

Defined in Control.Effect.Trace

Methods

eff :: (Trace :+: sig) (TraceByIgnoringC m) a -> TraceByIgnoringC m a

(MonadIO m, Carrier sig m) => Carrier (Trace :+: sig) (TraceByPrintingC m)

Defined in Control.Effect.Trace

Methods

eff :: (Trace :+: sig) (TraceByPrintingC m) a -> TraceByPrintingC m a

(HFunctor eff, Carrier sig m) => Carrier (eff :+: sig) (InterpretC eff m)

Defined in Control.Effect.Interpret

Methods

eff :: (eff :+: sig) (InterpretC eff m) a -> InterpretC eff m a

(Carrier sig m, Effect sig) => Carrier (State s :+: sig) (StateC s m)

Defined in Control.Effect.State.Strict

Methods

eff :: (State s :+: sig) (StateC s m) a -> StateC s m a

(Carrier sig m, Effect sig) => Carrier (State s :+: sig) (StateC s m)

Defined in Control.Effect.State.Lazy

Methods

eff :: (State s :+: sig) (StateC s m) a -> StateC s m a

Carrier sig m => Carrier (Reader r :+: sig) (ReaderC r m)

Defined in Control.Effect.Reader

Methods

eff :: (Reader r :+: sig) (ReaderC r m) a -> ReaderC r m a

(Carrier sig m, Effect sig, RandomGen g) => Carrier (Random :+: sig) (RandomC g m)

Defined in Control.Effect.Random

Methods

eff :: (Random :+: sig) (RandomC g m) a -> RandomC g m a

(Carrier sig m, Effect sig) => Carrier (Error e :+: sig) (ErrorC e m)

Defined in Control.Effect.Error

Methods

eff :: (Error e :+: sig) (ErrorC e m) a -> ErrorC e m a

Carrier sig m => Carrier (Resumable err :+: sig) (ResumableWithC err m)

Defined in Control.Effect.Resumable

Methods

eff :: (Resumable err :+: sig) (ResumableWithC err m) a -> ResumableWithC err m a

(Carrier sig m, Effect sig) => Carrier (Resumable err :+: sig) (ResumableC err m)

Defined in Control.Effect.Resumable

Methods

eff :: (Resumable err :+: sig) (ResumableC err m) a -> ResumableC err m a

(Monoid w, Carrier sig m, Effect sig) => Carrier (Writer w :+: sig) (WriterC w m)

Defined in Control.Effect.Writer

Methods

eff :: (Writer w :+: sig) (WriterC w m) a -> WriterC w m a

(HFunctor eff, Carrier sig m, Effect sig) => Carrier (eff :+: sig) (InterpretStateC eff s m)

Defined in Control.Effect.Interpret

Methods

eff :: (eff :+: sig) (InterpretStateC eff s m) a -> InterpretStateC eff s m a

class Member (sub :: (* -> *) -> * -> *) sup

Minimal complete definition

inj, prj

Instances

Member sub sub

Defined in Control.Effect.Sum

Methods

inj :: forall (m :: Type -> Type) a. sub m a -> sub m a

prj :: forall (m :: Type -> Type) a. sub m a -> Maybe (sub m a)

Member sub sup => Member sub (sub' :+: sup)

Defined in Control.Effect.Sum

Methods

inj :: forall (m :: Type -> Type) a. sub m a -> (sub' :+: sup) m a

prj :: forall (m :: Type -> Type) a. (sub' :+: sup) m a -> Maybe (sub m a)

Member sub (sub :+: sup)

Defined in Control.Effect.Sum

Methods

inj :: forall (m :: Type -> Type) a. sub m a -> (sub :+: sup) m a

prj :: forall (m :: Type -> Type) a. (sub :+: sup) m a -> Maybe (sub m a)

run :: PureC a -> a

Run an action exhausted of effects to produce its final result value.