Safe Haskell	None
Language	Haskell2010

Control.Effect.Sum

Synopsis

data (f :+: g) (m :: * -> *) k
- = L (f m k)
- | R (g m k)
handleSum :: (sig2 m a -> b) -> (sig1 m a -> b) -> (sig1 :+: sig2) m a -> b
class Member (sub :: (* -> *) -> * -> *) sup where
send :: (Member effect sig, Carrier sig m) => effect m (m a) -> m a

Documentation

data (f :+: g) (m :: * -> *) k infixr 4 Source #

Constructors

L (f m k)
R (g m k)

Instances

Member sub sup => Member sub (sub' :+: sup) Source #
Instance details Defined in Control.Effect.Sum Methods inj :: sub m a -> (sub' :+: sup) m a Source # prj :: (sub' :+: sup) m a -> Maybe (sub m a) Source #
Member sub (sub :+: sup) Source #
Instance details Defined in Control.Effect.Sum Methods inj :: sub m a -> (sub :+: sup) m a Source # prj :: (sub :+: sup) m a -> Maybe (sub m a) Source #
(Effect l, Effect r) => Effect (l :+: r) Source #
Instance details Defined in Control.Effect.Sum Methods handle :: Functor f => f () -> (forall x. f (m x) -> n (f x)) -> (l :+: r) m (m a) -> (l :+: r) n (n (f a)) Source #
(HFunctor l, HFunctor r) => HFunctor (l :+: r) Source #
Instance details Defined in Control.Effect.Sum Methods fmap' :: (a -> b) -> (l :+: r) m a -> (l :+: r) m b Source # hmap :: (forall x. m x -> n x) -> (l :+: r) m a -> (l :+: r) n a Source #
(Carrier sig m, Effect sig) => Carrier (Fail :+: sig) (FailC m) Source #
Instance details Defined in Control.Effect.Fail Methods ret :: a -> FailC m a Source # eff :: (Fail :+: sig) (FailC m) (FailC m a) -> FailC m a Source #
(Carrier sig m, MonadIO m) => Carrier (Resource :+: sig) (ResourceC m) Source #
Instance details Defined in Control.Effect.Resource Methods ret :: a -> ResourceC m a Source # eff :: (Resource :+: sig) (ResourceC m) (ResourceC m a) -> ResourceC m a Source #
(Carrier sig m, Effect sig, Monad m) => Carrier (Fresh :+: sig) (FreshC m) Source #
Instance details Defined in Control.Effect.Fresh Methods ret :: a -> FreshC m a Source # eff :: (Fresh :+: sig) (FreshC m) (FreshC m a) -> FreshC m a Source #
(Alternative m, Carrier sig m, Effect sig, Monad m) => Carrier (Cull :+: (NonDet :+: sig)) (CullC m) Source #
Instance details Defined in Control.Effect.Cull Methods ret :: a -> CullC m a Source # eff :: (Cull :+: (NonDet :+: sig)) (CullC m) (CullC m a) -> CullC m a Source #
(Alternative m, Carrier sig m, Effect sig, Monad m) => Carrier (Cut :+: (NonDet :+: sig)) (CutC m) Source #
Instance details Defined in Control.Effect.Cut Methods ret :: a -> CutC m a Source # eff :: (Cut :+: (NonDet :+: sig)) (CutC m) (CutC m a) -> CutC m a Source #
(Carrier sig m, Effect sig) => Carrier (Trace :+: sig) (TraceByReturningC m) Source #
Instance details Defined in Control.Effect.Trace Methods ret :: a -> TraceByReturningC m a Source # eff :: (Trace :+: sig) (TraceByReturningC m) (TraceByReturningC m a) -> TraceByReturningC m a Source #
Carrier sig m => Carrier (Trace :+: sig) (TraceByIgnoringC m) Source #
Instance details Defined in Control.Effect.Trace Methods ret :: a -> TraceByIgnoringC m a Source # eff :: (Trace :+: sig) (TraceByIgnoringC m) (TraceByIgnoringC m a) -> TraceByIgnoringC m a Source #
(MonadIO m, Carrier sig m) => Carrier (Trace :+: sig) (TraceByPrintingC m) Source #
Instance details Defined in Control.Effect.Trace Methods ret :: a -> TraceByPrintingC m a Source # eff :: (Trace :+: sig) (TraceByPrintingC m) (TraceByPrintingC m a) -> TraceByPrintingC m a Source #
(Alternative f, Carrier sig m, Effect sig, Traversable f, Monad f, Monad m) => Carrier (NonDet :+: sig) (OnceC f m) Source #
Instance details Defined in Control.Effect.NonDet Methods ret :: a -> OnceC f m a Source # eff :: (NonDet :+: sig) (OnceC f m) (OnceC f m a) -> OnceC f m a Source #
(Alternative f, Monad f, Traversable f, Carrier sig m, Effect sig, Applicative m) => Carrier (NonDet :+: sig) (AltC f m) Source #
Instance details Defined in Control.Effect.NonDet Methods ret :: a -> AltC f m a Source # eff :: (NonDet :+: sig) (AltC f m) (AltC f m a) -> AltC f m a Source #
(Carrier sig m, Effect sig, RandomGen g, Monad m) => Carrier (Random :+: sig) (RandomC g m) Source #
Instance details Defined in Control.Effect.Random Methods ret :: a -> RandomC g m a Source # eff :: (Random :+: sig) (RandomC g m) (RandomC g m a) -> RandomC g m a Source #
(Carrier sig m, Effect sig) => Carrier (State s :+: sig) (StateC s m) Source #
Instance details Defined in Control.Effect.State Methods ret :: a -> StateC s m a Source # eff :: (State s :+: sig) (StateC s m) (StateC s m a) -> StateC s m a Source #
(Carrier sig m, Monad m) => Carrier (Resumable err :+: sig) (ResumableWithC err m) Source #
Instance details Defined in Control.Effect.Resumable Methods ret :: a -> ResumableWithC err m a Source # eff :: (Resumable err :+: sig) (ResumableWithC err m) (ResumableWithC err m a) -> ResumableWithC err m a Source #
(Carrier sig m, Effect sig) => Carrier (Resumable err :+: sig) (ResumableC err m) Source #
Instance details Defined in Control.Effect.Resumable Methods ret :: a -> ResumableC err m a Source # eff :: (Resumable err :+: sig) (ResumableC err m) (ResumableC err m a) -> ResumableC err m a Source #
(Carrier sig m, Monad m) => Carrier (Reader r :+: sig) (ReaderC r m) Source #
Instance details Defined in Control.Effect.Reader Methods ret :: a -> ReaderC r m a Source # eff :: (Reader r :+: sig) (ReaderC r m) (ReaderC r m a) -> ReaderC r m a Source #
(Carrier sig m, Effect sig, Monad m) => Carrier (Error e :+: sig) (ErrorC e m) Source #
Instance details Defined in Control.Effect.Error Methods ret :: a -> ErrorC e m a Source # eff :: (Error e :+: sig) (ErrorC e m) (ErrorC e m a) -> ErrorC e m a Source #
(Monoid w, Carrier sig m, Effect sig, Functor m) => Carrier (Writer w :+: sig) (WriterC w m) Source #
Instance details Defined in Control.Effect.Writer Methods ret :: a -> WriterC w m a Source # eff :: (Writer w :+: sig) (WriterC w m) (WriterC w m a) -> WriterC w m a Source #
(Functor (f m), Functor (g m)) => Functor ((f :+: g) m) Source #
Instance details Defined in Control.Effect.Sum Methods fmap :: (a -> b) -> (f :+: g) m a -> (f :+: g) m b # (<$) :: a -> (f :+: g) m b -> (f :+: g) m a #
(Eq (f m k), Eq (g m k)) => Eq ((f :+: g) m k) Source #
Instance details Defined in Control.Effect.Sum Methods (==) :: (f :+: g) m k -> (f :+: g) m k -> Bool # (/=) :: (f :+: g) m k -> (f :+: g) m k -> Bool #
(Ord (f m k), Ord (g m k)) => Ord ((f :+: g) m k) Source #
Instance details Defined in Control.Effect.Sum Methods compare :: (f :+: g) m k -> (f :+: g) m k -> Ordering # (<) :: (f :+: g) m k -> (f :+: g) m k -> Bool # (<=) :: (f :+: g) m k -> (f :+: g) m k -> Bool # (>) :: (f :+: g) m k -> (f :+: g) m k -> Bool # (>=) :: (f :+: g) m k -> (f :+: g) m k -> Bool # max :: (f :+: g) m k -> (f :+: g) m k -> (f :+: g) m k # min :: (f :+: g) m k -> (f :+: g) m k -> (f :+: g) m k #
(Show (f m k), Show (g m k)) => Show ((f :+: g) m k) Source #
Instance details Defined in Control.Effect.Sum Methods showsPrec :: Int -> (f :+: g) m k -> ShowS # show :: (f :+: g) m k -> String # showList :: [(f :+: g) m k] -> ShowS #

handleSum :: (sig2 m a -> b) -> (sig1 m a -> b) -> (sig1 :+: sig2) m a -> b Source #

Lift algebras for either side of a sum into a single algebra on sums.

Note that the order of the functions is the opposite of members of the sum. This is more convenient for defining effect handlers as lambdas (especially using -XLambdaCase) on the right, enabling better error messaging when using typed holes than would be the case with a binding in a where clause.

class Member (sub :: (* -> *) -> * -> *) sup where Source #

Minimal complete definition

inj, prj

Methods

inj :: sub m a -> sup m a Source #

prj :: sup m a -> Maybe (sub m a) Source #

Instances

Member sub sub Source #
Instance details Defined in Control.Effect.Sum Methods inj :: sub m a -> sub m a Source # prj :: sub m a -> Maybe (sub m a) Source #
Member sub sup => Member sub (sub' :+: sup) Source #
Instance details Defined in Control.Effect.Sum Methods inj :: sub m a -> (sub' :+: sup) m a Source # prj :: (sub' :+: sup) m a -> Maybe (sub m a) Source #
Member sub (sub :+: sup) Source #
Instance details Defined in Control.Effect.Sum Methods inj :: sub m a -> (sub :+: sup) m a Source # prj :: (sub :+: sup) m a -> Maybe (sub m a) Source #

send :: (Member effect sig, Carrier sig m) => effect m (m a) -> m a Source #

Construct a request for an effect to be interpreted by some handler later on.