Struct CancelToken 

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

Cloneable cancellation flag shared between the apply worker and any number of signalling threads.

Clone is O(1) — every handle points at the same underlying AtomicBool. Marking the token cancelled from any handle is visible to every other handle on the next Self::is_cancelled poll.

Threading

Send + Sync is automatic: the inner Arc of AtomicBool is trivially shareable across threads. Construct on one thread, clone, and hand the clones to wherever they need to live.

Cost

Self::is_cancelled is a single Ordering::Relaxed atomic load and is cheap enough to call from the inner SQPK block loop. Self::cancel is one relaxed store. The token allocates one Arc-managed AtomicBool at construction; clones share it.

Implementations

impl CancelToken

pub fn new() -> Self

Construct a fresh, un-cancelled token.

pub fn cancel(&self)

Request cancellation.

Idempotent — calling this on an already-cancelled token is a no-op. The flip is immediately visible to every clone of this token.

pub fn is_cancelled(&self) -> bool

Returns true if Self::cancel has been called on any clone of this token.

Uses Ordering::Relaxed — the apply driver polls this in hot loops and only needs eventual visibility, not synchronisation with any other memory ops.

pub fn reset(&self)

Clear the cancellation flag.

Useful for retry-after-cancel scenarios where the consumer wants to reuse the same token (and therefore avoid re-wiring its clones) across multiple apply attempts. The flip is immediately visible to every clone.

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

Formats the value using the given formatter.

impl Default for CancelToken

fn default() -> CancelToken

Returns the “default value” for a type.