Struct HashSetDelay

pub struct HashSetDelay<K>
where
    K: Eq + Hash + Clone + Unpin,
{ /* private fields */ }

A simple hashset object coupled with a delay_queue which has entries that expire after a fixed time.

A HashSetDelay implements Stream which removes expired items from the map.

Implementations

impl<K> HashSetDelay<K>

where K: Eq + Hash + Clone + Unpin,

pub fn new(default_entry_timeout: Duration) -> Self

Creates a new instance of HashSetDelay.

pub fn with_capacity(default_entry_timeout: Duration, capacity: usize) -> Self

Creates an empty HashSetDelay with at least the specified capacity.

The hash map will be able to hold at least capacity elements without reallocating. This method is allowed to allocate for more elements than capacity. If capacity is 0, the hash map will not allocate.

pub fn insert(&mut self, key: K)

Insert an entry into the mapping. Entries will expire after the default_entry_timeout.

pub fn insert_at(&mut self, key: K, entry_duration: Duration)

Inserts an entry that will expire at a given instant. Panics if the duration is too far in the future.

pub fn update_timeout(&mut self, key: &K, timeout: Duration) -> bool

Updates the timeout for a given key. Returns true if the key existed, false otherwise.

Panics if the duration is too far in the future.

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

Returns true if the key exists, false otherwise.

pub fn len(&self) -> usize

Returns the length of the mapping.

pub fn is_empty(&self) -> bool

Returns true if the mapping is empty.

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

Removes a key from the map returning the value associated with the key that was in the map.

Return None if the key was not in the map.

pub fn clear(&mut self)

Removes all entries from the map.

pub fn iter(&self) -> impl Iterator<Item = &K>

Returns an iterator referencing all items in the set.

pub fn shrink_to_fit(&mut self)

Shrink the capacity of the underlying hash map to fit the current elements.

pub fn shrink_to(&mut self, capacity: usize)

Shrink the capacity of the underlying data structures to hold a specific number of elements

pub fn deadline(&self, key: &K) -> Option<Instant>

Find the approximate (to the ms) time that a specific entry will expire

pub fn poll_expired( &mut self, cx: &mut Context<'_>, ) -> Poll<Option<Result<K, String>>>

Removes expired entries and returns them.

Trait Implementations

impl<K> Debug for HashSetDelay<K>

where K: Eq + Hash + Clone + Unpin + Debug,

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

Formats the value using the given formatter.

impl<K> Default for HashSetDelay<K>

where K: Eq + Hash + Clone + Unpin,

fn default() -> Self

Returns the “default value” for a type.

impl<K> Stream for HashSetDelay<K>

where K: Eq + Hash + Clone + Unpin,

type Item = Result<K, String>

Values yielded by the stream.

fn poll_next( self: Pin<&mut Self>, cx: &mut Context<'_>, ) -> Poll<Option<Self::Item>>

Attempt to pull out the next value of this stream, registering the current task for wakeup if the value is not yet available, and returning None if the stream is exhausted.

fn size_hint(&self) -> (usize, Option<usize>)

Returns the bounds on the remaining length of the stream.