Struct LRUCache 

pub struct LRUCache<K: Ord + Clone, V, const MAX_SIZE: usize> {
    inner: BTreeMap<K, Node<K, V>>,
    head: Option<K>,
    tail: Option<K>,
}

An Least Recently Used Cache with capacity MAX_SIZE.

Fields

inner: BTreeMap<K, Node<K, V>>

head: Option<K>

tail: Option<K>

Implementations

impl<K: Ord + Clone, V, const MAX_SIZE: usize> LRUCache<K, V, MAX_SIZE>

fn attach(&mut self, k: K) -> &mut Node<K, V>

fn detach(&mut self, prev: Option<K>, next: Option<K>)

pub const fn new() -> Self

Makes a new, empty LRUCache.

Does not allocate anything on its own.

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

Returns a mutable reference to the value corresponding to the key and update the last access time.

pub fn get_or_insert_with<E>( &mut self, k: K, f: impl FnOnce() -> Result<V, E>, ) -> Result<&mut V, E>

Inserts the value computed with f into the LRUCache if it is not present, then returns a reference to the value in the LRUCache.

fn __put(&mut self, k: K, v: V) -> &mut Node<K, V>

pub fn put(&mut self, k: K, v: V)

Inserts a key-value pair into the LRUCache.

If the map did have this key present, the value is updated. The key is not updated, though; this matters for types that can be == without being identical.

If the cache size is overflowed after insertion, evict the oldest accessed entry.

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

Removes a key from the LRUCache, returning the stored value if the key was previously in the LRUCache.

The key may be any borrowed form of the LRUCache’s key type, but the ordering on the borrowed form must match the ordering on the key type.

pub fn retain(&mut self, f: impl FnMut(&K, &mut V) -> bool)

Retains only the elements specified by the predicate. In other words, remove all pairs (k, v) for which f(&k, &mut v) returns false.

pub fn iter_mut(&mut self) -> impl Iterator<Item = (&K, &mut V)>

Iterates over the key-value pairs in the LRUCache.

Trait Implementations

impl<K: Ord + Clone, V, const MAX_SIZE: usize> Default for LRUCache<K, V, MAX_SIZE>

fn default() -> Self

Returns the “default value” for a type.