Copyright	(c) Michael Szvetits 2020
License	BSD3 (see the file LICENSE)
Maintainer	typedbyte@qualified.name
Stability	stable
Portability	portable
Safe Haskell	None
Language	Haskell2010

Control.Effect.Map.Lazy

Contents

Interpreter Implementation
Tagged Interpretations
Untagged Interpretations

Description

Lazy interpretations of the Map' effect.

If you don't require disambiguation of multiple map effects (i.e., you only have one map effect in your monadic context), you usually need the untagged interpretations.

Synopsis

data LazyMap k v m a
clear :: Monad m => LazyMap k v m ()
lookup :: (Monad m, Ord k) => k -> LazyMap k v m (Maybe v)
update :: (Monad m, Ord k) => k -> Maybe v -> LazyMap k v m ()
runMap' :: forall tag k v m a. Monad m => (Map' tag k v `Via` LazyMap k v) m a -> m a
runMap :: Monad m => (Map k v `Via` LazyMap k v) m a -> m a

Interpreter Implementation

data LazyMap k v m a Source #

The lazy interpreter of the map effect. This type implements the Map' type class in a lazy manner.

When interpreting the effect, you usually don't interact with this type directly, but instead use one of its corresponding interpretation functions.

Instances

Instances details

(Monad m, Ord k2) => Map' (tag :: k1) k2 v (LazyMap k2 v m) Source #
Instance details Defined in Control.Effect.Map.Lazy Methods clear' :: LazyMap k2 v m () Source # lookup' :: k2 -> LazyMap k2 v m (Maybe v) Source # update' :: k2 -> Maybe v -> LazyMap k2 v m () Source #
MonadBase b m => MonadBase b (LazyMap k v m) Source #
Instance details Defined in Control.Effect.Map.Lazy Methods liftBase :: b α -> LazyMap k v m α #
MonadBaseControl b m => MonadBaseControl b (LazyMap k v m) Source #
Instance details Defined in Control.Effect.Map.Lazy Associated Types type StM (LazyMap k v m) a # Methods liftBaseWith :: (RunInBase (LazyMap k v m) b -> b a) -> LazyMap k v m a # restoreM :: StM (LazyMap k v m) a -> LazyMap k v m a #
MonadTrans (LazyMap k v) Source #
Instance details Defined in Control.Effect.Map.Lazy Methods lift :: Monad m => m a -> LazyMap k v m a #
MonadTransControl (LazyMap k v) Source #
Instance details Defined in Control.Effect.Map.Lazy Associated Types type StT (LazyMap k v) a # Methods liftWith :: Monad m => (Run (LazyMap k v) -> m a) -> LazyMap k v m a # restoreT :: Monad m => m (StT (LazyMap k v) a) -> LazyMap k v m a #
Monad m => Monad (LazyMap k v m) Source #
Instance details Defined in Control.Effect.Map.Lazy Methods (>>=) :: LazyMap k v m a -> (a -> LazyMap k v m b) -> LazyMap k v m b # (>>) :: LazyMap k v m a -> LazyMap k v m b -> LazyMap k v m b # return :: a -> LazyMap k v m a #
Functor m => Functor (LazyMap k v m) Source #
Instance details Defined in Control.Effect.Map.Lazy Methods fmap :: (a -> b) -> LazyMap k v m a -> LazyMap k v m b # (<$) :: a -> LazyMap k v m b -> LazyMap k v m a #
Monad m => Applicative (LazyMap k v m) Source #
Instance details Defined in Control.Effect.Map.Lazy Methods pure :: a -> LazyMap k v m a # (<>) :: LazyMap k v m (a -> b) -> LazyMap k v m a -> LazyMap k v m b # liftA2 :: (a -> b -> c) -> LazyMap k v m a -> LazyMap k v m b -> LazyMap k v m c # (>) :: LazyMap k v m a -> LazyMap k v m b -> LazyMap k v m b # (<*) :: LazyMap k v m a -> LazyMap k v m b -> LazyMap k v m a #
MonadIO m => MonadIO (LazyMap k v m) Source #
Instance details Defined in Control.Effect.Map.Lazy Methods liftIO :: IO a -> LazyMap k v m a #
type StT (LazyMap k v) a Source #
Instance details Defined in Control.Effect.Map.Lazy type StT (LazyMap k v) a = StT (StateT (Map k v)) a
type StM (LazyMap k v m) a Source #
Instance details Defined in Control.Effect.Map.Lazy type StM (LazyMap k v m) a = StM (StateT (Map k v) m) a

clear :: Monad m => LazyMap k v m () Source #

Deletes all key-value pairs from the map.

lookup :: (Monad m, Ord k) => k -> LazyMap k v m (Maybe v) Source #

Searches for a value that corresponds to a given key. Returns Nothing if the key cannot be found.

update :: (Monad m, Ord k) => k -> Maybe v -> LazyMap k v m () Source #

Updates the value that corresponds to a given key. Passing Nothing as the updated value removes the key-value pair from the map.

Tagged Interpretations

runMap' Source #

Arguments

:: forall tag k v m a. Monad m
=> (Map' tag k v `Via` LazyMap k v) m a	The program whose map effect should be handled.
-> m a	The program with its map effect handled.

Runs the map effect, initialized with an empty map.

Untagged Interpretations

runMap :: Monad m => (Map k v `Via` LazyMap k v) m a -> m a Source #

The untagged version of runMap'.