Enum Shareable

pub enum Shareable<T> {
    Owned(T),
    Shared(Arc<T>),
}

Wraps an object and provides mutable access to it.

The point is that sometimes we want to stop mutability and proliferate reference-counted pointers to it.

This happens in a controlled environment, in the with_shared method closure argument. All reference-counted pointers are expected to be dropped until that closure finishes.

Variants

Owned(T)

Shared(Arc<T>)

Implementations

impl<T> Shareable<T>

pub fn new(t: T) -> Self

pub fn into_inner(self) -> T

Destroys the object and returns the contents.

impl<T> Shareable<T>

pub fn with_shared<F, R>(&mut self, f: F) -> R

where F: FnOnce(Arc<T>) -> R,

The main functionality of Shared.

Temporarily makes the object immutable, and creates a Rc pointer to the contents, which can then be cloned.

Important restriction: all Rc pointers creates from the one given to the closure f must be dropped before its execution ends. Otherwise the operation will panic.

Trait Implementations

impl<T> Default for Shareable<T>

where T: Default,

fn default() -> Self

Returns the “default value” for a type.

impl<T> Deref for Shareable<T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<T> DerefMut for Shareable<T>

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.