Safe Haskell	None
Language	Haskell2010

Control.Effect.Fresh

Synopsis

data Fresh m k
- = Fresh (Int -> k)
- | Reset (m b) (b -> k)
fresh :: (Member Fresh sig, Carrier sig m) => m Int
resetFresh :: (Member Fresh sig, Carrier sig m) => m a -> m a
runFresh :: Functor m => FreshC m a -> m a
newtype FreshC m a = FreshC {
- runFreshC :: StateC Int m a
}

Documentation

data Fresh m k Source #

Constructors

Fresh (Int -> k)
Reset (m b) (b -> k)

Instances

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

fresh :: (Member Fresh sig, Carrier sig m) => m Int Source #

Produce a fresh (i.e. unique) Int.

run (runFresh (replicateM n fresh)) == nub (run (runFresh (replicateM n fresh)))

resetFresh :: (Member Fresh sig, Carrier sig m) => m a -> m a Source #

Reset the fresh counter after running a computation.

run (runFresh (resetFresh (replicateM m fresh) *> replicateM n fresh)) == run (runFresh (replicateM n fresh))

runFresh :: Functor m => FreshC m a -> m a Source #

Run a Fresh effect counting up from 0.

run (runFresh (replicateM n fresh)) == [0..pred n]

run (runFresh (replicateM n fresh *> pure b)) == b

newtype FreshC m a Source #

Constructors

FreshC
Fields runFreshC :: StateC Int m a

Instances

MonadTrans FreshC Source #
Instance details Defined in Control.Effect.Fresh Methods lift :: Monad m => m a -> FreshC m a #
Monad m => Monad (FreshC m) Source #
Instance details Defined in Control.Effect.Fresh Methods (>>=) :: FreshC m a -> (a -> FreshC m b) -> FreshC m b # (>>) :: FreshC m a -> FreshC m b -> FreshC m b # return :: a -> FreshC m a # fail :: String -> FreshC m a #
Functor m => Functor (FreshC m) Source #
Instance details Defined in Control.Effect.Fresh Methods fmap :: (a -> b) -> FreshC m a -> FreshC m b # (<$) :: a -> FreshC m b -> FreshC m a #
MonadFail m => MonadFail (FreshC m) Source #
Instance details Defined in Control.Effect.Fresh Methods fail :: String -> FreshC m a #
Monad m => Applicative (FreshC m) Source #
Instance details Defined in Control.Effect.Fresh Methods pure :: a -> FreshC m a # (<>) :: FreshC m (a -> b) -> FreshC m a -> FreshC m b # liftA2 :: (a -> b -> c) -> FreshC m a -> FreshC m b -> FreshC m c # (>) :: FreshC m a -> FreshC m b -> FreshC m b # (<*) :: FreshC m a -> FreshC m b -> FreshC m a #
MonadIO m => MonadIO (FreshC m) Source #
Instance details Defined in Control.Effect.Fresh Methods liftIO :: IO a -> FreshC m a #
(Alternative m, Monad m) => Alternative (FreshC m) Source #
Instance details 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, Monad m) => MonadPlus (FreshC m) Source #
Instance details Defined in Control.Effect.Fresh Methods mzero :: FreshC m a # mplus :: FreshC m a -> FreshC m a -> FreshC m a #
(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 #