Struct PassAgedCache 

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

A bounded LRU cache whose entries also leave once IDLE_PASSES layout passes go by without a lookup of them. A scrolling list then keeps the measurements of the texts it shows, not of every text it has shown up to the bound.

Implementations

impl<K, V> PassAgedCache<K, V>

where K: Eq + Hash,

pub fn with_capacity_at_least_one(capacity: usize) -> Self

pub fn len(&self) -> usize

pub fn is_empty(&self) -> bool

pub fn clear(&mut self)

Drops every entry and gives back the storage they took.

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

where K: Borrow<Q>, Q: Hash + Eq + ?Sized,

The value under key, marked used in the current pass.

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

Stores value under key, returning the entry it replaced or the least recently used one it pushed out.

pub fn pop_lru(&mut self) -> Option<(K, V)>

pub fn begin_pass(&mut self, dropped: impl FnMut(V))

Starts a layout pass: drops the entries no lookup asked for in the last IDLE_PASSES passes, least recently used first, handing each dropped value to dropped. It stops at the first entry still in use, so it costs one comparison when nothing has gone idle.