Struct ArcCache 

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

Adaptive Replacement Cache with configurable capacity and optional per-entry TTL.

Type parameters

• K: key type – must be Eq + Hash + Clone.
• V: value type.

Implementations

impl<K, V> ArcCache<K, V>

where K: Eq + Hash + Clone,

pub fn new(cap: usize) -> Self

Create a new ArcCache with the given capacity.

Capacity must be at least 1; a capacity of 0 is treated as 1 internally.

pub fn p(&self) -> usize

Return the current adaptive target p.

pub fn len(&self) -> usize

Total live-data entries (|t1| + |t2|).

pub fn is_empty(&self) -> bool

Return true if no live entries are cached.

pub fn cap(&self) -> usize

Cache capacity.

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

Look up key and return a reference to its value, promoting as needed.

Expired entries are lazily removed and treated as misses.

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

Insert key -> value into the cache (no TTL).

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

Insert key -> value into the cache with a TTL.

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

Read a value without promoting it.

Checks t1 and t2 but does NOT move entries or trigger ghost adaptation. Expired entries return None (removal happens on next mutable access).

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

Return true if key is present in t1 or t2 and not expired (without promotion).

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

Remove the entry for key from the cache.

Returns the value if it was present in t1 or t2. Also removes any ghost entry from b1/b2.

pub fn clear(&mut self)

Remove all entries from the cache (live + ghost).

pub fn resize(&mut self, new_cap: usize)

Dynamically resize the cache capacity.

If new_cap is smaller than the current live count, entries are evicted via the REPLACE routine until the count fits.

Trait Implementations

impl<K, V> Cache<K, V> for ArcCache<K, V>

where K: Eq + Hash + Clone,

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

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

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

Insert or update key -> value without a TTL.

fn put_with_ttl(&mut self, key: K, value: V, ttl: Duration) -> Option<V>

Insert or update key -> value with a time-to-live.

fn len(&self) -> usize

Return the number of live entries currently in the cache.

fn cap(&self) -> usize

Return the maximum number of entries the cache can hold.

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

Remove the entry associated with key, returning its value if present.

fn clear(&mut self)

Remove all entries from the cache.

fn peek(&self, key: &K) -> Option<&V>

Look up key without updating access metadata (no promotion).

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

Return true if key is present in the cache (without promotion).

fn resize(&mut self, new_cap: usize)

Dynamically resize the cache capacity.

fn values(&self) -> Vec<&V>

Return all live (non-expired) values currently stored in the cache.

fn is_empty(&self) -> bool

Return true if the cache holds no entries.

fn get_or_insert(&mut self, key: K, default: impl FnOnce() -> V) -> &V

where K: Clone,

Return &V for key, inserting default() if the key is absent.

fn warm(&mut self, iter: impl IntoIterator<Item = (K, V)>)

Pre-populate the cache with (key, value) pairs from an iterator.

impl<K: Debug, V> Debug for ArcCache<K, V>

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

Formats the value using the given formatter.