Safe Haskell	None
Language	Haskell2010

Control.Carrier.Choose.Church

Contents

Choose carrier
Choose effect

Description

A carrier for Choose effects (nondeterminism without failure).

Under the hood, it uses a Church-encoded binary tree to avoid the problems associated with a naïve list-based implementation (see "ListT done right").

Since: 1.0.0.0

Synopsis

runChoose :: (m b -> m b -> m b) -> (a -> m b) -> ChooseC m a -> m b
runChooseS :: (Semigroup b, Applicative m) => (a -> m b) -> ChooseC m a -> m b
newtype ChooseC m a = ChooseC (forall b. (m b -> m b -> m b) -> (a -> m b) -> m b)
module Control.Effect.Choose

Choose carrier

runChoose :: (m b -> m b -> m b) -> (a -> m b) -> ChooseC m a -> m b Source #

Run a Choose effect with continuations respectively interpreting <|> and pure.

runChoose fork leaf (pure a <|> b) = leaf a `fork` runChoose fork leaf b

Since: 1.0.0.0

runChooseS :: (Semigroup b, Applicative m) => (a -> m b) -> ChooseC m a -> m b Source #

Run a Choose effect, mapping results into a Semigroup.

Since: 1.0.0.0

newtype ChooseC m a Source #

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

Since: 1.0.0.0

Constructors

ChooseC (forall b. (m b -> m b -> m b) -> (a -> m b) -> m b)

Instances

MonadTrans ChooseC Source #
Instance details Defined in Control.Carrier.Choose.Church Methods lift :: Monad m => m a -> ChooseC m a #
Monad (ChooseC m) Source #
Instance details Defined in Control.Carrier.Choose.Church Methods (>>=) :: ChooseC m a -> (a -> ChooseC m b) -> ChooseC m b # (>>) :: ChooseC m a -> ChooseC m b -> ChooseC m b # return :: a -> ChooseC m a # fail :: String -> ChooseC m a #
Functor (ChooseC m) Source #
Instance details Defined in Control.Carrier.Choose.Church Methods fmap :: (a -> b) -> ChooseC m a -> ChooseC m b # (<$) :: a -> ChooseC m b -> ChooseC m a #
MonadFix m => MonadFix (ChooseC m) Source #	Separate fixpoints are computed for each branch.
Instance details Defined in Control.Carrier.Choose.Church Methods mfix :: (a -> ChooseC m a) -> ChooseC m a #
MonadFail m => MonadFail (ChooseC m) Source #
Instance details Defined in Control.Carrier.Choose.Church Methods fail :: String -> ChooseC m a #
Applicative (ChooseC m) Source #
Instance details Defined in Control.Carrier.Choose.Church Methods pure :: a -> ChooseC m a # (<>) :: ChooseC m (a -> b) -> ChooseC m a -> ChooseC m b # liftA2 :: (a -> b -> c) -> ChooseC m a -> ChooseC m b -> ChooseC m c # (>) :: ChooseC m a -> ChooseC m b -> ChooseC m b # (<*) :: ChooseC m a -> ChooseC m b -> ChooseC m a #
MonadIO m => MonadIO (ChooseC m) Source #
Instance details Defined in Control.Carrier.Choose.Church Methods liftIO :: IO a -> ChooseC m a #
Algebra sig m => Algebra (Choose :+: sig) (ChooseC m) Source #
Instance details Defined in Control.Carrier.Choose.Church Methods alg :: Functor ctx => Handler ctx n (ChooseC m) -> (Choose :+: sig) n a -> ctx () -> ChooseC m (ctx a) Source #

Choose effect

module Control.Effect.Choose