Struct alloc::rc::WeakExperimental

pub struct Weak<T> {
    // some fields omitted
}

A weak version of Rc<T>.

Weak references do not count when determining if the inner value should be dropped.

See the module level documentation for more.

Methods

impl<T> Weak<T>

fn upgrade(&self) -> Option<Rc<T>>

Upgrades a weak reference to a strong reference.

Upgrades the Weak<T> reference to an Rc<T>, if possible.

Returns None if there were no strong references and the data was destroyed.

Examples

use std::rc::Rc;

let five = Rc::new(5i);

let weak_five = five.downgrade();

let strong_five: Option<Rc<_>> = weak_five.upgrade();

Trait Implementations

impl<T> Drop for Weak<T>

fn drop(&mut self)

Drops the Weak<T>.

This will decrement the weak reference count.

Examples

use std::rc::Rc;

{
    let five = Rc::new(5i);
    let weak_five = five.downgrade();

    // stuff

    drop(weak_five); // explict drop
}
{
    let five = Rc::new(5i);
    let weak_five = five.downgrade();

    // stuff

} // implicit drop

impl<T> Clone for Weak<T>

fn clone(&self) -> Weak<T>

Makes a clone of the Weak<T>.

This increases the weak reference count.

Examples

use std::rc::Rc;

let weak_five = Rc::new(5i).downgrade();

weak_five.clone();

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

impl<T: Show> Show for Weak<T>

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