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Dependencies base (>=4.7 && <5), containers, generic-lens, lens, stm [details]
License MIT
Copyright 2018 Arbor Networks
Author Arbor Networks
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Source repo head: git clone
Uploaded by arbornetworks at 2018-09-26T05:06:40Z


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Readme for arbor-lru-cache-

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A thread-safe LRU cache library.


To use the cache:

main :: IO
main = do
  -- Provide a configuration that includes how many simultaneous in
  -- flight requests are allowed and now many entries the cache can store
  let config = A.CacheConfig
        { A.maxRequestsInFlight = 1
        , A.maxOccupancy        = 1

  -- Create a cache providing the config and functions that handle retrieval
  -- and eviction.
  cache <- A.makeCache config retrieve evict

  -- Perform your lookups
  _ <- A.lookup 1 cache
  _ <- A.lookup 2 cache
  _ <- A.lookup 3 cache

  return ()

-- Implement value retrieval function.  If the same key is looked up multiple
-- times, the cache guarantees that the retrieve function is called only once
-- for that key up until it is evicted.
retrieve :: Int -> IO String
retrieve mk = ...

-- Perform any cleanup that should occur when an entry is evicted
-- Please be aware that if your code is concurrent, the eviction function may
-- be called whilst the you code is concurrently using a value it has looked up.
-- Your code is wholly responsible for ensuring this case still works.
evict :: Int -> String -> IO ()
evict mk mv = ...