Using

Using core.cache

note: see the page on Including core.cache before you begin this section

For any of the cache implementations, the pattern of usage is as follows:

    (require '[clojure.core.cache :as cache])
	
    (def C (cache/fifo-cache-factory {:a 1, :b 2})
	
    (if (cache/has? C :c)
      (cache/hit C :c)
      (cache/miss C :c 42))
	
    ;=> {:a 1, :b 2, :c 42}
	
    (cache/evict C :b)
	
    ;=> {:a 1}

Using the has?/hit/miss pattern ensures that the thresholding and eviction logic for each implementation works properly. Avoid this pattern at your own risk.

Builtin cache implementations

core.cache comes with a number of builtin immutable cache implementations, including (click through for specific information):

• FIFO cache
• LRU cache
• LU cache
• TTL cache
• LIRS cache
• Function-backed cache
• Naive cache

The core.cache implementations are backed by any map-like object. Additionally, each cache implements the Clojure map behaviors and can therefore serve as special maps or even as backing stores for other cache implementations. For caches taking a limit argument, the eviction policies tend not to apply until the limit has been exceeded.

Extending core.cache

See the section on creating custom caches for more information.