Safe Haskell	None
Language	Haskell2010

Control.Effect.Cull

Synopsis

data Cull m k = Cull (m a) (a -> k)
cull :: (Carrier sig m, Member Cull sig) => m a -> m a
runCull :: Alternative m => CullC m a -> m a
newtype CullC m a = CullC {
- runCullC :: ReaderC Bool (NonDetC m) a
}
runNonDetOnce :: (Alternative f, Carrier sig m, Effect sig) => OnceC m a -> m (f a)
newtype OnceC m a = OnceC {
- runOnceC :: CullC (NonDetC m) a
}

Documentation

data Cull m k Source #

Cull effects are used with NonDet to provide control over branching.

Constructors

Cull (m a) (a -> k)

Instances

Effect Cull Source #
Instance details Defined in Control.Effect.Cull Methods handle :: Functor f => f () -> (forall x. f (m x) -> n (f x)) -> Cull m (m a) -> Cull n (n (f a)) Source #
HFunctor Cull Source #
Instance details Defined in Control.Effect.Cull Methods fmap' :: (a -> b) -> Cull m a -> Cull m b Source # hmap :: (forall x. m x -> n x) -> Cull m a -> Cull n a Source #
Functor (Cull m) Source #
Instance details Defined in Control.Effect.Cull Methods fmap :: (a -> b) -> Cull m a -> Cull m b # (<$) :: a -> Cull m b -> Cull m a #
(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 #

cull :: (Carrier sig m, Member Cull sig) => m a -> m a Source #

Cull nondeterminism in the argument, returning at most one result.

run (runNonDet (runCull (cull (pure a <|> pure b)))) == [a]

run (runNonDet (runCull (cull (pure a <|> pure b) <|> pure c))) == [a, c]

run (runNonDet (runCull (cull (asum (map pure (repeat a)))))) == [a]

runCull :: Alternative m => CullC m a -> m a Source #

Run a Cull effect. Branches outside of any cull block will not be pruned.

run (runNonDet (runCull (pure a <|> pure b))) == [a, b]

newtype CullC m a Source #

Constructors

CullC
Fields runCullC :: ReaderC Bool (NonDetC m) a

Instances

MonadTrans CullC Source #
Instance details Defined in Control.Effect.Cull Methods lift :: Monad m => m a -> CullC m a #
Monad (CullC m) Source #
Instance details Defined in Control.Effect.Cull Methods (>>=) :: CullC m a -> (a -> CullC m b) -> CullC m b # (>>) :: CullC m a -> CullC m b -> CullC m b # return :: a -> CullC m a # fail :: String -> CullC m a #
Functor (CullC m) Source #
Instance details Defined in Control.Effect.Cull Methods fmap :: (a -> b) -> CullC m a -> CullC m b # (<$) :: a -> CullC m b -> CullC m a #
MonadFail m => MonadFail (CullC m) Source #
Instance details Defined in Control.Effect.Cull Methods fail :: String -> CullC m a #
Applicative (CullC m) Source #
Instance details Defined in Control.Effect.Cull Methods pure :: a -> CullC m a # (<>) :: CullC m (a -> b) -> CullC m a -> CullC m b # liftA2 :: (a -> b -> c) -> CullC m a -> CullC m b -> CullC m c # (>) :: CullC m a -> CullC m b -> CullC m b # (<*) :: CullC m a -> CullC m b -> CullC m a #
MonadIO m => MonadIO (CullC m) Source #
Instance details Defined in Control.Effect.Cull Methods liftIO :: IO a -> CullC m a #
Alternative (CullC m) Source #
Instance details Defined in Control.Effect.Cull Methods empty :: CullC m a # (<\|>) :: CullC m a -> CullC m a -> CullC m a # some :: CullC m a -> CullC m [a] # many :: CullC m a -> CullC m [a] #
MonadPlus (CullC m) Source #
Instance details Defined in Control.Effect.Cull Methods mzero :: CullC m a # mplus :: CullC m a -> CullC m a -> CullC m a #
(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 #

runNonDetOnce :: (Alternative f, Carrier sig m, Effect sig) => OnceC m a -> m (f a) Source #

Run a NonDet effect, returning the first successful result in an Alternative functor.

Unlike runNonDet, this will terminate immediately upon finding a solution.

run (runNonDetOnce (asum (map pure (repeat a)))) == [a]

run (runNonDetOnce (asum (map pure (repeat a)))) == Just a

newtype OnceC m a Source #

Constructors

OnceC
Fields runOnceC :: CullC (NonDetC m) a

Instances

Monad (OnceC m) Source #
Instance details Defined in Control.Effect.Cull Methods (>>=) :: OnceC m a -> (a -> OnceC m b) -> OnceC m b # (>>) :: OnceC m a -> OnceC m b -> OnceC m b # return :: a -> OnceC m a # fail :: String -> OnceC m a #
Functor (OnceC m) Source #
Instance details Defined in Control.Effect.Cull Methods fmap :: (a -> b) -> OnceC m a -> OnceC m b # (<$) :: a -> OnceC m b -> OnceC m a #
MonadFail m => MonadFail (OnceC m) Source #
Instance details Defined in Control.Effect.Cull Methods fail :: String -> OnceC m a #
Applicative (OnceC m) Source #
Instance details Defined in Control.Effect.Cull Methods pure :: a -> OnceC m a # (<>) :: OnceC m (a -> b) -> OnceC m a -> OnceC m b # liftA2 :: (a -> b -> c) -> OnceC m a -> OnceC m b -> OnceC m c # (>) :: OnceC m a -> OnceC m b -> OnceC m b # (<*) :: OnceC m a -> OnceC m b -> OnceC m a #
MonadIO m => MonadIO (OnceC m) Source #
Instance details Defined in Control.Effect.Cull Methods liftIO :: IO a -> OnceC m a #
Alternative (OnceC m) Source #
Instance details Defined in Control.Effect.Cull Methods empty :: OnceC m a # (<\|>) :: OnceC m a -> OnceC m a -> OnceC m a # some :: OnceC m a -> OnceC m [a] # many :: OnceC m a -> OnceC m [a] #
MonadPlus (OnceC m) Source #
Instance details Defined in Control.Effect.Cull Methods mzero :: OnceC m a # mplus :: OnceC m a -> OnceC m a -> OnceC m a #
(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 #