This module contains a mutable wrapping of an LRU in the IO monad, providing atomic access in a concurrent environment. All calls preserve the same semantics as those in Data.Cache.LRU, but perform updates in place.
This module contains the internal implementation details. It's
possible to put an
AtomicLRU into a bad state with this module.
It is highly recommended that the external interface,
Data.Cache.LRU.IO, be used instead.
- newtype AtomicLRU key val = C (MVar (LRU key val))
- newAtomicLRU :: Ord key => Maybe Integer -> IO (AtomicLRU key val)
- fromList :: Ord key => Maybe Integer -> [(key, val)] -> IO (AtomicLRU key val)
- toList :: Ord key => AtomicLRU key val -> IO [(key, val)]
- maxSize :: AtomicLRU key val -> IO (Maybe Integer)
- insert :: Ord key => key -> val -> AtomicLRU key val -> IO ()
- lookup :: Ord key => key -> AtomicLRU key val -> IO (Maybe val)
- delete :: Ord key => key -> AtomicLRU key val -> IO (Maybe val)
- pop :: Ord key => AtomicLRU key val -> IO (Maybe (key, val))
- size :: AtomicLRU key val -> IO Int
- modifyAtomicLRU :: (LRU key val -> LRU key val) -> AtomicLRU key val -> IO ()
- modifyMVar_' :: MVar a -> (a -> IO a) -> IO ()
- modifyMVar' :: MVar a -> (a -> IO (a, b)) -> IO b
Make a new AtomicLRU that will not grow beyond the optional maximum size, if specified.
Build a new LRU from the optional maximum size and list of
fromList for the semantics.
Retrieve a list view of an AtomicLRU. See
toList for the
Insert a key/value pair into an AtomicLRU. See
Look up a key in an AtomicLRU. See
lookup for the
Remove an item from an AtomicLRU. Returns the value for the removed key, if it was present
Remove the least-recently accessed item from an AtomicLRU. Returns the (key, val) pair removed, if one was present.
Returns the number of elements the AtomicLRU currently contains.
Given a function that takes an
LRU and returns one of the
same type, use it to modify the contents of this AtomicLRU.
A version of
modifyMVar_ that forces the result of the
function application to WHNF.