Struct CancelToken 

pub struct CancelToken(/* private fields */);

Available on crate feature runtime only.

A token that can be used to cancel multiple operations at once.

When CancelToken::cancel is called, all operations that have been registered with this token will be cancelled.

It is also possible to use CancelToken::wait to wait until the token is cancelled, which can be useful for implementing timeouts or other cancellation-based logic.

To associate a future with this cancel token, use the with_cancel combinator from the FutureExt trait, which requires nightly feature future-combinator.

Implementations

impl CancelToken

pub fn new() -> CancelToken

Create a new cancel token.

pub fn cancel(self)

Cancel all operations registered with this token.

pub fn is_cancelled(&self) -> bool

Check if this token has been cancelled.

pub fn register<T>(&self, key: &Key<T>)

where T: OpCode,

Register an operation with this token.

If the token has already been cancelled, the operation will be cancelled immediately. Usually this method should not be used directly, but rather through the with_cancel combinator, which requires nightly feature future-combinator.

Multiple registrations of the same key does nothing, and the key will only be cancelled once.

pub fn wait(self) -> WaitFuture

Wait until this token is cancelled.

pub async fn current() -> Option<CancelToken>

Try to get the current cancel token associated with the future.

This is done by checking if the current context has a cancel token associated with it. This will only work with nightly feature future-combinator turned on; otherwise, None is always returned.

Trait Implementations

impl Clone for CancelToken

fn clone(&self) -> CancelToken

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CancelToken

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

Formats the value using the given formatter.

impl Default for CancelToken

fn default() -> CancelToken

Returns the “default value” for a type.

impl PartialEq for CancelToken

fn eq(&self, other: &CancelToken) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for CancelToken