Struct LruCache 

pub struct LruCache<K, V> { /* private fields */ }

A generic fixed-capacity LRU (Least Recently Used) cache.

The cache stores up to capacity key-value pairs. When full, the least recently accessed entry is evicted to make room for new ones.

Implementations

impl<K: Clone + Eq + Hash, V> LruCache<K, V>

pub fn new(capacity: usize) -> Self

Create a new LRU cache with the given capacity.

Panics

Panics if capacity is 0.

pub fn get(&mut self, key: &K) -> Option<&V>

Look up a key, returning a reference to the value if present.

This promotes the entry to the most recently used position.

pub fn contains(&self, key: &K) -> bool

Check whether a key exists without promoting it.

pub fn insert(&mut self, key: K, value: V) -> Option<(K, V)>

Insert a key-value pair. If the key already exists, update the value. Returns the evicted key-value pair if the cache was full.

pub fn remove(&mut self, key: &K) -> Option<V>

Remove a key from the cache, returning its value if present.

pub fn len(&self) -> usize

Return the number of entries currently in the cache.

pub fn is_empty(&self) -> bool

Check if the cache is empty.

pub fn capacity(&self) -> usize

Return the capacity.

pub fn stats(&self) -> &CacheStats

Return a reference to the cache statistics.

pub fn clear(&mut self)

Clear all entries.

Trait Implementations

impl<K: Clone + Eq + Hash + Debug, V> Debug for LruCache<K, V>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.