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
- inj :: sub m a -> sup m a
- prj :: sup m a -> Maybe (sub m a)
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, MonadIO m) => Carrier (Resource :+: sig) (ResourceC m) Source #
Instance details Defined in Control.Effect.Resource Methods eff :: (Resource :+: sig) (ResourceC m) (ResourceC m a) -> ResourceC m a Source # ret :: a -> ResourceC m a Source #
(Carrier sig m, Effect sig) => Carrier (NonDet :+: sig) (NonDetC m) Source #
Instance details Defined in Control.Effect.NonDet Methods eff :: (NonDet :+: sig) (NonDetC m) (NonDetC m a) -> NonDetC m a Source # ret :: a -> NonDetC m a Source #
(Carrier sig m, Effect sig) => Carrier (NonDet :+: sig) (OnceC m) Source #
Instance details Defined in Control.Effect.Cull Methods eff :: (NonDet :+: sig) (OnceC m) (OnceC m a) -> OnceC m a Source # ret :: a -> OnceC m a Source #
(Carrier sig m, Effect sig) => Carrier (Fresh :+: sig) (FreshC m) Source #
Instance details Defined in Control.Effect.Fresh Methods eff :: (Fresh :+: sig) (FreshC m) (FreshC m a) -> FreshC m a Source # ret :: a -> FreshC m a Source #
(Carrier sig m, Effect sig) => Carrier (Fail :+: sig) (FailC m) Source #
Instance details Defined in Control.Effect.Fail Methods eff :: (Fail :+: sig) (FailC m) (FailC m a) -> FailC m a Source # ret :: a -> FailC m a Source #
(Carrier sig m, Effect sig) => Carrier (Cut :+: (NonDet :+: sig)) (CutC m) Source #
Instance details Defined in Control.Effect.Cut Methods eff :: (Cut :+: (NonDet :+: sig)) (CutC m) (CutC m a) -> CutC m a Source # ret :: a -> CutC m a Source #
(Carrier sig m, Effect sig) => Carrier (Cull :+: (NonDet :+: sig)) (CullC m) Source #
Instance details Defined in Control.Effect.Cull Methods eff :: (Cull :+: (NonDet :+: sig)) (CullC m) (CullC m a) -> CullC m a Source # ret :: a -> CullC m a Source #
(Carrier sig m, Effect sig) => Carrier (Trace :+: sig) (TraceByReturningC m) Source #
Instance details Defined in Control.Effect.Trace Methods eff :: (Trace :+: sig) (TraceByReturningC m) (TraceByReturningC m a) -> TraceByReturningC m a Source # ret :: a -> TraceByReturningC m a Source #
Carrier sig m => Carrier (Trace :+: sig) (TraceByIgnoringC m) Source #
Instance details Defined in Control.Effect.Trace Methods eff :: (Trace :+: sig) (TraceByIgnoringC m) (TraceByIgnoringC m a) -> TraceByIgnoringC m a Source # ret :: a -> TraceByIgnoringC m a Source #
(MonadIO m, Carrier sig m) => Carrier (Trace :+: sig) (TraceByPrintingC m) Source #
Instance details Defined in Control.Effect.Trace Methods eff :: (Trace :+: sig) (TraceByPrintingC m) (TraceByPrintingC m a) -> TraceByPrintingC m a Source # ret :: a -> TraceByPrintingC m a Source #
(Carrier sig m, Effect sig) => Carrier (State s :+: sig) (StateC s m) Source #
Instance details Defined in Control.Effect.State.Strict Methods eff :: (State s :+: sig) (StateC s m) (StateC s m a) -> StateC s m a Source # ret :: a -> StateC s m a Source #
(Carrier sig m, Effect sig) => Carrier (State s :+: sig) (StateC s m) Source #
Instance details Defined in Control.Effect.State.Lazy Methods eff :: (State s :+: sig) (StateC s m) (StateC s m a) -> StateC s m a Source # ret :: a -> StateC s m a Source #
Carrier sig m => Carrier (Reader r :+: sig) (ReaderC r m) Source #
Instance details Defined in Control.Effect.Reader Methods eff :: (Reader r :+: sig) (ReaderC r m) (ReaderC r m a) -> ReaderC r m a Source # ret :: a -> ReaderC r m a Source #
(Carrier sig m, Effect sig, RandomGen g) => Carrier (Random :+: sig) (RandomC g m) Source #
Instance details Defined in Control.Effect.Random Methods eff :: (Random :+: sig) (RandomC g m) (RandomC g m a) -> RandomC g m a Source # ret :: a -> RandomC g m a Source #
(Carrier sig m, Effect sig) => Carrier (Error e :+: sig) (ErrorC e m) Source #
Instance details Defined in Control.Effect.Error Methods eff :: (Error e :+: sig) (ErrorC e m) (ErrorC e m a) -> ErrorC e m a Source # ret :: a -> ErrorC e m a Source #
Carrier sig m => Carrier (Resumable err :+: sig) (ResumableWithC err m) Source #
Instance details Defined in Control.Effect.Resumable Methods eff :: (Resumable err :+: sig) (ResumableWithC err m) (ResumableWithC err m a) -> ResumableWithC err m a Source # ret :: 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 eff :: (Resumable err :+: sig) (ResumableC err m) (ResumableC err m a) -> ResumableC err m a Source # ret :: a -> ResumableC err m a Source #
(Monoid w, Carrier sig m, Effect sig) => Carrier (Writer w :+: sig) (WriterC w m) Source #
Instance details Defined in Control.Effect.Writer Methods eff :: (Writer w :+: sig) (WriterC w m) (WriterC w m a) -> WriterC w m a Source # ret :: 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 #

Deprecated: Carriers are now monads, so handleSum is obsolete: define handlers with do-notation and pattern-matching on L and R

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 #

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.