Data.LruCache

Pure API to an LRU cache.

Documentation

data LruCache k v

LRU cache based on hashing. The times of access are stored in a monotonically increasing Int64, when that time is at maxbound the cache is emptied.

Instances

Functor (LruCache k)

Methods

fmap :: (a -> b) -> LruCache k a -> LruCache k b

(<$) :: a -> LruCache k b -> LruCache k a

Foldable (LruCache k)

Methods

fold :: Monoid m => LruCache k m -> m

foldMap :: Monoid m => (a -> m) -> LruCache k a -> m

foldr :: (a -> b -> b) -> b -> LruCache k a -> b

foldr' :: (a -> b -> b) -> b -> LruCache k a -> b

foldl :: (b -> a -> b) -> b -> LruCache k a -> b

foldl' :: (b -> a -> b) -> b -> LruCache k a -> b

foldr1 :: (a -> a -> a) -> LruCache k a -> a

foldl1 :: (a -> a -> a) -> LruCache k a -> a

toList :: LruCache k a -> [a]

null :: LruCache k a -> Bool

length :: LruCache k a -> Int

elem :: Eq a => a -> LruCache k a -> Bool

maximum :: Ord a => LruCache k a -> a

minimum :: Ord a => LruCache k a -> a

sum :: Num a => LruCache k a -> a

product :: Num a => LruCache k a -> a

Traversable (LruCache k)

Methods

traverse :: Applicative f => (a -> f b) -> LruCache k a -> f (LruCache k b)

sequenceA :: Applicative f => LruCache k (f a) -> f (LruCache k a)

mapM :: Monad m => (a -> m b) -> LruCache k a -> m (LruCache k b)

sequence :: Monad m => LruCache k (m a) -> m (LruCache k a)

(Eq v, Ord k, Hashable k) => Eq (LruCache k v)

Methods

(==) :: LruCache k v -> LruCache k v -> Bool

(/=) :: LruCache k v -> LruCache k v -> Bool

(Show k, Show v) => Show (LruCache k v)

Methods

showsPrec :: Int -> LruCache k v -> ShowS

show :: LruCache k v -> String

showList :: [LruCache k v] -> ShowS

(NFData k, NFData v) => NFData (LruCache k v)

Methods

rnf :: LruCache k v -> ()

type Priority = Int64

Logical time at which an element was last accessed.

empty :: Int -> LruCache k v

Create an empty LruCache of the given size.

insert :: (Hashable k, Ord k) => k -> v -> LruCache k v -> LruCache k v

Insert an element into the LruCache.

insertView :: (Hashable k, Ord k) => k -> v -> LruCache k v -> (Maybe (k, v), LruCache k v)

Insert an element into the LruCache returning the evicted element if any.

When the logical clock reaches its maximum value and all values are evicted Nothing is returned.

lookup :: (Hashable k, Ord k) => k -> LruCache k v -> Maybe (v, LruCache k v)

Lookup an element in an LruCache and mark it as the least recently accessed.