Crate generational_lru
source · [−]Expand description
Crate providing a 100% safe, generational arena based LRUCache implementation.
Usage:
use generational_lru::lrucache::{LRUCache, CacheError};
let capacity = 5;
let mut lru_cache = LRUCache::<i32, i32>::with_capacity(capacity);
assert_eq!(lru_cache.query(&0), Err(CacheError::CacheMiss));
for ele in 0..capacity {
let x = ele as i32;
assert!(lru_cache.insert(x, x).is_ok());
}
for ele in 0..capacity {
let x = ele as i32;
assert_eq!(lru_cache.query(&x), Ok(&x));
}
let x = capacity as i32;
assert!(lru_cache.insert(x, x).is_ok());
assert_eq!(lru_cache.query(&x), Ok(&x));
assert_eq!(lru_cache.query(&0), Err(CacheError::CacheMiss));
let x = capacity as i32 / 2;
assert_eq!(lru_cache.remove(&x), Ok(x));
assert_eq!(lru_cache.query(&x), Err(CacheError::CacheMiss));
assert_eq!(lru_cache.remove(&x), Err(CacheError::CacheMiss));
// zero capacity LRUCache is unusable
let mut lru_cache = LRUCache::<i32, i32>::with_capacity(0);
assert!(matches!(
lru_cache.insert(0, 0),
Err(CacheError::CacheBroken(_))
));