Struct futures::task::Context

pub struct Context<'a> { /* fields omitted */ }

Information about the currently-running task.

Contexts are always tied to the stack, since they are set up specifically when performing a single poll step on a task.

Methods

impl<'a> Context<'a>

pub fn waker(&self) -> Waker

Get the Waker associated with the current task.

The waker can subsequently be used to wake up the task when some event of interest has happened.

pub fn with_waker(&'b mut self, waker: &'b Waker) -> Context<'b>

Produce a context like the current one, but using the given waker instead.

This advanced method is primarily used when building "internal schedulers" within a task, where you want to provide some customized wakeup logic.

pub fn with_locals(&'b mut self, map: &'b mut LocalMap) -> Context<'b>

Produce a context like the current one, but using the given task locals instead.

This advanced method is primarily used when building "internal schedulers" within a task.

impl<'a> Context<'a>

pub fn new(
    map: &'a mut LocalMap,
    waker: &'a Waker,
    executor: &'a mut (Executor + 'a)
) -> Context<'a>

Create a new task context.

Task contexts are always equipped with:

• Task-local data
• A means of waking the task
• A means of spawning new tasks, i.e. an executor

pub fn executor(&mut self) -> &mut Executor

Get the default executor associated with this task.

This method is useful primarily if you want to explicitly handle spawn failures.

pub fn spawn<F>(&mut self, f: F) where
    F: Future<Item = (), Error = Never> + 'static + Send, 

Spawn a future onto the default executor.

Panics

This method will panic if the default executor is unable to spawn. To handle executor errors, use executor() instead.

Trait Implementations

impl<'a> Debug for Context<'a>

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

Formats the value using the given formatter.