CacheMap

CacheMap is a data structure for concurrently caching values.

the cache function will look up a value in the map, or generate and store a new one using the provided function

Example

``` use cachemap::CacheMap;

let m = CacheMap::new();

let fst = m.cache("key", || 5u32).asref(); let snd = m.cache("key", || 7u32).asref();

asserteq!(*fst, *snd); asserteq!(*fst, 5u32); ```

Features 🌞

• can cache values concurrently (using &CacheMap<K,V> rather than &mut CacheMap<K,V>)
• returned references use the map's lifetime, so clients can avoid smart pointers
• clients can optionally get Arc<V> pointers, in case values need to outlive the map
• values can be addes as Arc<V>, allowing unsized values, and re-using Arc<V>s from elsewhere

MisFeatures 💧

A cache with a bad policy is another name for a memory leak

this map provides only one way to remove things from the cache: drop the entire map.