Control.Effect.NonDet

Documentation

data NonDet (m :: * -> *) k

Constructors

Empty

Choose (Bool -> k)

Instances

Effect NonDet

Defined in Control.Effect.NonDet

Methods

handle :: Functor f => f () -> (forall x. f (m x) -> n (f x)) -> NonDet m (m a) -> NonDet n (n (f a))

HFunctor NonDet

Defined in Control.Effect.NonDet

Methods

fmap' :: (a -> b) -> NonDet m a -> NonDet m b

hmap :: (forall x. m x -> n x) -> NonDet m a -> NonDet n a

Functor (NonDet m)

Defined in Control.Effect.NonDet

Methods

fmap :: (a -> b) -> NonDet m a -> NonDet m b

(<$) :: a -> NonDet m b -> NonDet m a

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

Defined in Control.Effect.NonDet

Methods

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

class Applicative f => Alternative (f :: Type -> Type) where

A monoid on applicative functors.

If defined, some and many should be the least solutions of the equations:

• some v = (:) <$> v <*> many v

• many v = some v <|> pure []

Minimal complete definition

empty, (<|>)

Methods

empty :: f a

The identity of <|>

(<|>) :: f a -> f a -> f a infixl 3

An associative binary operation

some :: f a -> f [a]

One or more.

many :: f a -> f [a]

Zero or more.

Instances

Alternative []

Since: base-2.1

Defined in GHC.Base

Methods

empty :: [a]

(<|>) :: [a] -> [a] -> [a]

some :: [a] -> [[a]]

many :: [a] -> [[a]]

Alternative Maybe

Since: base-2.1

Defined in GHC.Base

Methods

empty :: Maybe a

(<|>) :: Maybe a -> Maybe a -> Maybe a

some :: Maybe a -> Maybe [a]

many :: Maybe a -> Maybe [a]

Alternative IO

Since: base-4.9.0.0

Defined in GHC.Base

Methods

empty :: IO a

(<|>) :: IO a -> IO a -> IO a

some :: IO a -> IO [a]

many :: IO a -> IO [a]

Alternative Option

Since: base-4.9.0.0

Defined in Data.Semigroup

Methods

empty :: Option a

(<|>) :: Option a -> Option a -> Option a

some :: Option a -> Option [a]

many :: Option a -> Option [a]

Alternative ZipList

Since: base-4.11.0.0

Defined in Control.Applicative

Methods

empty :: ZipList a

(<|>) :: ZipList a -> ZipList a -> ZipList a

some :: ZipList a -> ZipList [a]

many :: ZipList a -> ZipList [a]

Alternative ReadP

Since: base-4.6.0.0

Defined in Text.ParserCombinators.ReadP

Methods

empty :: ReadP a

(<|>) :: ReadP a -> ReadP a -> ReadP a

some :: ReadP a -> ReadP [a]

many :: ReadP a -> ReadP [a]

Alternative P

Since: base-4.5.0.0

Defined in Text.ParserCombinators.ReadP

Methods

empty :: P a

(<|>) :: P a -> P a -> P a

some :: P a -> P [a]

many :: P a -> P [a]

MonadPlus m => Alternative (WrappedMonad m)

Since: base-2.1

Defined in Control.Applicative

Methods

empty :: WrappedMonad m a

(<|>) :: WrappedMonad m a -> WrappedMonad m a -> WrappedMonad m a

some :: WrappedMonad m a -> WrappedMonad m [a]

many :: WrappedMonad m a -> WrappedMonad m [a]

ArrowPlus a => Alternative (ArrowMonad a)

Since: base-4.6.0.0

Defined in Control.Arrow

Methods

empty :: ArrowMonad a a0

(<|>) :: ArrowMonad a a0 -> ArrowMonad a a0 -> ArrowMonad a a0

some :: ArrowMonad a a0 -> ArrowMonad a [a0]

many :: ArrowMonad a a0 -> ArrowMonad a [a0]

Alternative (Proxy :: Type -> Type)

Since: base-4.9.0.0

Defined in Data.Proxy

Methods

empty :: Proxy a

(<|>) :: Proxy a -> Proxy a -> Proxy a

some :: Proxy a -> Proxy [a]

many :: Proxy a -> Proxy [a]

Alternative m => Alternative (ResourceC m)

Defined in Control.Effect.Resource

Methods

empty :: ResourceC m a

(<|>) :: ResourceC m a -> ResourceC m a -> ResourceC m a

some :: ResourceC m a -> ResourceC m [a]

many :: ResourceC m a -> ResourceC m [a]

Alternative (NonDetC m)

Defined in Control.Effect.NonDet

Methods

empty :: NonDetC m a

(<|>) :: NonDetC m a -> NonDetC m a -> NonDetC m a

some :: NonDetC m a -> NonDetC m [a]

many :: NonDetC m a -> NonDetC m [a]

Alternative m => Alternative (LiftC m)

Defined in Control.Effect.Lift

Methods

empty :: LiftC m a

(<|>) :: LiftC m a -> LiftC m a -> LiftC m a

some :: LiftC m a -> LiftC m [a]

many :: LiftC m a -> LiftC m [a]

(Alternative m, Monad m) => Alternative (FreshC m)

Defined in Control.Effect.Fresh

Methods

empty :: FreshC m a

(<|>) :: FreshC m a -> FreshC m a -> FreshC m a

some :: FreshC m a -> FreshC m [a]

many :: FreshC m a -> FreshC m [a]

Alternative m => Alternative (FailC m)

Defined in Control.Effect.Fail

Methods

empty :: FailC m a

(<|>) :: FailC m a -> FailC m a -> FailC m a

some :: FailC m a -> FailC m [a]

many :: FailC m a -> FailC m [a]

Alternative (CutC m)

Defined in Control.Effect.Cut

Methods

empty :: CutC m a

(<|>) :: CutC m a -> CutC m a -> CutC m a

some :: CutC m a -> CutC m [a]

many :: CutC m a -> CutC m [a]

Alternative (OnceC m)

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]

Alternative (CullC m)

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]

(Alternative m, Monad m) => Alternative (TraceByReturningC m)

Defined in Control.Effect.Trace

Methods

empty :: TraceByReturningC m a

(<|>) :: TraceByReturningC m a -> TraceByReturningC m a -> TraceByReturningC m a

some :: TraceByReturningC m a -> TraceByReturningC m [a]

many :: TraceByReturningC m a -> TraceByReturningC m [a]

Alternative m => Alternative (TraceByIgnoringC m)

Defined in Control.Effect.Trace

Methods

empty :: TraceByIgnoringC m a

(<|>) :: TraceByIgnoringC m a -> TraceByIgnoringC m a -> TraceByIgnoringC m a

some :: TraceByIgnoringC m a -> TraceByIgnoringC m [a]

many :: TraceByIgnoringC m a -> TraceByIgnoringC m [a]

Alternative m => Alternative (TraceByPrintingC m)

Defined in Control.Effect.Trace

Methods

empty :: TraceByPrintingC m a

(<|>) :: TraceByPrintingC m a -> TraceByPrintingC m a -> TraceByPrintingC m a

some :: TraceByPrintingC m a -> TraceByPrintingC m [a]

many :: TraceByPrintingC m a -> TraceByPrintingC m [a]

(ArrowZero a, ArrowPlus a) => Alternative (WrappedArrow a b)

Since: base-2.1

Defined in Control.Applicative

Methods

empty :: WrappedArrow a b a0

(<|>) :: WrappedArrow a b a0 -> WrappedArrow a b a0 -> WrappedArrow a b a0

some :: WrappedArrow a b a0 -> WrappedArrow a b [a0]

many :: WrappedArrow a b a0 -> WrappedArrow a b [a0]

Alternative f => Alternative (Ap f)

Since: base-4.12.0.0

Defined in Data.Monoid

Methods

empty :: Ap f a

(<|>) :: Ap f a -> Ap f a -> Ap f a

some :: Ap f a -> Ap f [a]

many :: Ap f a -> Ap f [a]

Alternative f => Alternative (Alt f)

Since: base-4.8.0.0

Defined in Data.Semigroup.Internal

Methods

empty :: Alt f a

(<|>) :: Alt f a -> Alt f a -> Alt f a

some :: Alt f a -> Alt f [a]

many :: Alt f a -> Alt f [a]

Alternative m => Alternative (IdentityT m)

Defined in Control.Monad.Trans.Identity

Methods

empty :: IdentityT m a

(<|>) :: IdentityT m a -> IdentityT m a -> IdentityT m a

some :: IdentityT m a -> IdentityT m [a]

many :: IdentityT m a -> IdentityT m [a]

(Functor m, Monad m, Error e) => Alternative (ErrorT e m)

Defined in Control.Monad.Trans.Error

Methods

empty :: ErrorT e m a

(<|>) :: ErrorT e m a -> ErrorT e m a -> ErrorT e m a

some :: ErrorT e m a -> ErrorT e m [a]

many :: ErrorT e m a -> ErrorT e m [a]

Alternative m => Alternative (ReaderT r m)

Defined in Control.Monad.Trans.Reader

Methods

empty :: ReaderT r m a

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

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

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

(Alternative m, Monad m) => Alternative (StateC s m)

Defined in Control.Effect.State.Strict

Methods

empty :: StateC s m a

(<|>) :: StateC s m a -> StateC s m a -> StateC s m a

some :: StateC s m a -> StateC s m [a]

many :: StateC s m a -> StateC s m [a]

(Alternative m, Monad m) => Alternative (StateC s m)

Defined in Control.Effect.State.Lazy

Methods

empty :: StateC s m a

(<|>) :: StateC s m a -> StateC s m a -> StateC s m a

some :: StateC s m a -> StateC s m [a]

many :: StateC s m a -> StateC s 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) => Alternative (RandomC g m)

Defined in Control.Effect.Random

Methods

empty :: RandomC g m a

(<|>) :: RandomC g m a -> RandomC g m a -> RandomC g m a

some :: RandomC g m a -> RandomC g m [a]

many :: RandomC g m a -> RandomC g m [a]

Alternative m => Alternative (InterpretC eff m)

Defined in Control.Effect.Interpret

Methods

empty :: InterpretC eff m a

(<|>) :: InterpretC eff m a -> InterpretC eff m a -> InterpretC eff m a

some :: InterpretC eff m a -> InterpretC eff m [a]

many :: InterpretC eff m a -> InterpretC eff m [a]

Alternative m => Alternative (ErrorC e m)

Defined in Control.Effect.Error

Methods

empty :: ErrorC e m a

(<|>) :: ErrorC e m a -> ErrorC e m a -> ErrorC e m a

some :: ErrorC e m a -> ErrorC e m [a]

many :: ErrorC e m a -> ErrorC e m [a]

Alternative m => Alternative (ResumableWithC err m)

Defined in Control.Effect.Resumable

Methods

empty :: ResumableWithC err m a

(<|>) :: ResumableWithC err m a -> ResumableWithC err m a -> ResumableWithC err m a

some :: ResumableWithC err m a -> ResumableWithC err m [a]

many :: ResumableWithC err m a -> ResumableWithC err m [a]

Alternative m => Alternative (ResumableC err m)

Defined in Control.Effect.Resumable

Methods

empty :: ResumableC err m a

(<|>) :: ResumableC err m a -> ResumableC err m a -> ResumableC err m a

some :: ResumableC err m a -> ResumableC err m [a]

many :: ResumableC err m a -> ResumableC err m [a]

(Alternative m, Monad m) => Alternative (WriterC w m)

Defined in Control.Effect.Writer

Methods

empty :: WriterC w m a

(<|>) :: WriterC w m a -> WriterC w m a -> WriterC w m a

some :: WriterC w m a -> WriterC w m [a]

many :: WriterC w m a -> WriterC w m [a]

(Alternative f, Alternative g) => Alternative (Product f g)

Since: base-4.9.0.0

Defined in Data.Functor.Product

Methods

empty :: Product f g a

(<|>) :: Product f g a -> Product f g a -> Product f g a

some :: Product f g a -> Product f g [a]

many :: Product f g a -> Product f g [a]

(Alternative m, Monad m) => Alternative (InterpretStateC eff s m)

Defined in Control.Effect.Interpret

Methods

empty :: InterpretStateC eff s m a

(<|>) :: InterpretStateC eff s m a -> InterpretStateC eff s m a -> InterpretStateC eff s m a

some :: InterpretStateC eff s m a -> InterpretStateC eff s m [a]

many :: InterpretStateC eff s m a -> InterpretStateC eff s m [a]

(Alternative f, Applicative g) => Alternative (Compose f g)

Since: base-4.9.0.0

Defined in Data.Functor.Compose

Methods

empty :: Compose f g a

(<|>) :: Compose f g a -> Compose f g a -> Compose f g a

some :: Compose f g a -> Compose f g [a]

many :: Compose f g a -> Compose f g [a]

runNonDet :: (Alternative f, Applicative m) => NonDetC m a -> m (f a)

Run a NonDet effect, collecting all branches’ results into an Alternative functor.

Using '[]' as the Alternative functor will produce all results, while Maybe will return only the first. However, unlike runNonDetOnce, this will still enumerate the entire search space before returning, meaning that it will diverge for infinite search spaces, even when using Maybe.

run (runNonDet (pure a)) == [a]

run (runNonDet (pure a)) == Just a

newtype NonDetC m a

A carrier for NonDet effects based on Ralf Hinze’s design described in Deriving Backtracking Monad Transformers.

Constructors

NonDetC

Fields

• runNonDetC :: forall b. (a -> m b -> m b) -> m b -> m b

  A higher-order function receiving two parameters: a function to combine each solution with the rest of the solutions, and an action to run when no results are produced.

Instances

MonadTrans NonDetC

Defined in Control.Effect.NonDet

Methods

lift :: Monad m => m a -> NonDetC m a

Monad (NonDetC m)

Defined in Control.Effect.NonDet

Methods

(>>=) :: NonDetC m a -> (a -> NonDetC m b) -> NonDetC m b

(>>) :: NonDetC m a -> NonDetC m b -> NonDetC m b

return :: a -> NonDetC m a

fail :: String -> NonDetC m a

Functor (NonDetC m)

Defined in Control.Effect.NonDet

Methods

fmap :: (a -> b) -> NonDetC m a -> NonDetC m b

(<$) :: a -> NonDetC m b -> NonDetC m a

MonadFail m => MonadFail (NonDetC m)

Defined in Control.Effect.NonDet

Methods

fail :: String -> NonDetC m a

Applicative (NonDetC m)

Defined in Control.Effect.NonDet

Methods

pure :: a -> NonDetC m a

(<*>) :: NonDetC m (a -> b) -> NonDetC m a -> NonDetC m b

liftA2 :: (a -> b -> c) -> NonDetC m a -> NonDetC m b -> NonDetC m c

(*>) :: NonDetC m a -> NonDetC m b -> NonDetC m b

(<*) :: NonDetC m a -> NonDetC m b -> NonDetC m a

MonadIO m => MonadIO (NonDetC m)

Defined in Control.Effect.NonDet

Methods

liftIO :: IO a -> NonDetC m a

Alternative (NonDetC m)

Defined in Control.Effect.NonDet

Methods

empty :: NonDetC m a

(<|>) :: NonDetC m a -> NonDetC m a -> NonDetC m a

some :: NonDetC m a -> NonDetC m [a]

many :: NonDetC m a -> NonDetC m [a]

MonadPlus (NonDetC m)

Defined in Control.Effect.NonDet

Methods

mzero :: NonDetC m a

mplus :: NonDetC m a -> NonDetC m a -> NonDetC m a

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

Defined in Control.Effect.NonDet

Methods

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