Control.Eff.Fresh

Create unique Enumerable values.

Documentation

data Fresh v where

Create unique Enumerable values.

Constructors

Fresh :: Fresh Int

Instances

(MonadBase m m, LiftedBase m r) => MonadBaseControl m (Eff (Fresh ': r))

Defined in Control.Eff.Fresh

Associated Types

type StM (Eff (Fresh ': r)) a :: Type

Methods

liftBaseWith :: (RunInBase (Eff (Fresh ': r)) m -> m a) -> Eff (Fresh ': r) a

restoreM :: StM (Eff (Fresh ': r)) a -> Eff (Fresh ': r) a

Handle Fresh (Int -> r)

Given a continuation and requests, respond to them

Defined in Control.Eff.Fresh

Methods

handle :: (v -> Int -> r) -> Fresh v -> Int -> r

type StM (Eff (Fresh ': r)) a

Defined in Control.Eff.Fresh

type StM (Eff (Fresh ': r)) a = StM (Eff r) (a, Int)

withFresh :: Monad m => a -> Int -> m (a, Int)

Embed a pure value. Note that this is a specialized form of State's and we could have reused it.

fresh :: Member Fresh r => Eff r Int

Produce a value that has not been previously produced.

runFresh' :: Int -> Eff (Fresh ': r) w -> Eff r w

Run an effect requiring unique values.