Struct WeakSignal 

pub struct WeakSignal<Args, R = (), C = DefaultCombiner, G = i32>
where
    Args: Clone + 'static,
    R: 'static,
    C: Combiner<R> + 'static,
    G: Ord + Send + Sync + 'static,
{ /* private fields */ }

A weak reference to a signal’s slots. Useful for allowing slots to maintain a persistant reference to their owning signal without causing a memory leak.

Example

use signals2::*;

let sig: Signal<()> = Signal::new();
let weak_sig = sig.weak();
sig.connect(move || {
    // if we had captured a cloned sig here it would cause a memory leak.
    // Signals maintain strong references to their slot functions, so a slot function
    // should not maintain a strong reference to its own signal or else a memory leak
    // will occur.
    weak_sig.upgrade().unwrap().connect(|| println!("Hello, world!"));
});
 
sig.emit(); // prints nothing
sig.emit(); // prints "Hello, world!" once
sig.emit(); // prints "Hello, world!" twice
// etc...

Implementations

impl<Args, R, C, G> WeakSignal<Args, R, C, G>

where Args: Clone + 'static, R: 'static, C: Combiner<R> + 'static, G: Ord + Send + Sync + 'static,

pub fn upgrade(&self) -> Option<Signal<Args, R, C, G>>

Returns Some(sig) where sig is the singal that the weak signal was created from. If the original signal (and all other clones of it) have been dropped, returns None.

Trait Implementations

impl<Args, R, C, G> Clone for WeakSignal<Args, R, C, G>

where Args: Clone + 'static, R: 'static, C: Combiner<R> + 'static, G: Ord + Send + Sync + 'static,

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.