Struct WeakSender 

pub struct WeakSender<T> { /* private fields */ }

A sender that does not keep the channel open.

When every Sender is dropped and only WeakSenders remain, the channel is closed for the receiver. A WeakSender sends nothing itself: upgrade turns it into a Sender while one exists.

use nuclei::sync::mpsc;

let (tx, _rx) = mpsc::channel::<i32>(15);
let weak = tx.downgrade();
assert!(weak.upgrade().is_some());
drop(tx);
assert!(weak.clone().upgrade().is_none());

Progress

clone, drop, strong_count and weak_count are wait-free. upgrade is lock-free, not wait-free: it is a compare-and-swap on the sender count that retries when a sender was cloned or dropped meanwhile.

Implementations

impl<T> WeakSender<T>

pub fn upgrade(&self) -> Option<Sender<T>>

Tries to turn the weak sender into a Sender.

Returns Some while at least one Sender (or OwnedPermit) is alive, and None once the last is gone.

pub fn strong_count(&self) -> usize

How many Sender handles exist.

pub fn weak_count(&self) -> usize

How many WeakSender handles exist.

Trait Implementations

impl<T> Clone for WeakSender<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T> Debug for WeakSender<T>

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

Formats the value using the given formatter.

impl<T> Drop for WeakSender<T>

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.