Struct CancellationToken 

pub struct CancellationToken { /* private fields */ }

Thread-safe cancellation token for query execution.

Uses an AtomicBool behind an Arc so cloning is O(1) and every clone observes the same cancellation flag. Once CancellationToken::cancel has been called, every subsequent CancellationToken::check returns QueryCancelled until CancellationToken::reset is called.

Implementations

impl CancellationToken

pub fn new() -> Self

pub fn cancel(&self)

Signal cancellation. Subsequent Self::check / Self::is_cancelled observe the flag as set across all clones of this token.

pub fn reset(&self)

Clear the cancellation signal for the next query. Operators holding a clone of this token through their lifetime see the reset on the next check.

pub fn is_cancelled(&self) -> bool

pub fn check(&self) -> Result<(), QueryCancelled>

Return QueryCancelled if cancellation was signalled. Ok(()) otherwise.

Designed for the inner loop of every operator: a single relaxed-ordered atomic load on the happy path.

Trait Implementations

impl Clone for CancellationToken

fn clone(&self) -> CancellationToken

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CancellationToken

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

Formats the value using the given formatter.

impl Default for CancellationToken

fn default() -> CancellationToken

Returns the “default value” for a type.