Struct futures::task::TaskRc

pub struct TaskRc<A> { /* fields omitted */ }

A reference to a piece of data that's accessible only within a specific Task.

This data is Send even when A is not Sync, because the data stored within is accessed in a single-threaded way. The thread accessing it may change over time, if the task migrates, so A must be Send.

Methods

impl<A> TaskRc<A>

fn new(a: A) -> TaskRc<A>

Inserts a new piece of task-local data into this task, returning a reference to it.

Ownership of the data will be transferred to the task, and the data will be destroyed when the task itself is destroyed. The returned value can be passed to the with method to get a reference back to the original data.

Note that the returned handle is cloneable and copyable and can be sent to other futures which will be associated with the same task. All futures will then have access to this data when passed the reference back.

Panics

This function will panic if a task is not currently running.

fn with<F, R>(&self, f: F) -> R where F: FnOnce(&A) -> R

Operate with a reference to the underlying data.

This method should be passed a handle previously returned by Task::insert. That handle, when passed back into this method, will retrieve a reference to the original data.

Panics

This method will panic if a task is not currently running or if self does not belong to the task that is currently running. That is, if another task generated the data handle passed in, this method will panic.

Trait Implementations

impl<A: Send> Send for TaskRc<A>

impl<A: Sync> Sync for TaskRc<A>

impl<A> Clone for TaskRc<A>

fn clone(&self) -> TaskRc<A>

Returns a copy of the value.

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

Performs copy-assignment from source.