Struct ScheduleInfo

#[non_exhaustive]
pub struct ScheduleInfo {
    pub woken_while_running: bool,
}

Extra scheduling information that can be passed to the scheduling function.

The data source of this struct is directly from the actual implementation of the crate itself, different from Runnable’s metadata, which is managed by the caller.

Examples

use async_task::{Runnable, ScheduleInfo, WithInfo};
use std::sync::{Arc, Mutex};

// The future inside the task.
let future = async {
    println!("Hello, world!");
};

// If the task gets woken up while running, it will be sent into this channel.
let (s, r) = flume::unbounded();
// Otherwise, it will be placed into this slot.
let lifo_slot = Arc::new(Mutex::new(None));
let schedule = move |runnable: Runnable, info: ScheduleInfo| {
    if info.woken_while_running {
        s.send(runnable).unwrap()
    } else {
        let last = lifo_slot.lock().unwrap().replace(runnable);
        if let Some(last) = last {
            s.send(last).unwrap()
        }
    }
};

// Create the actual scheduler to be spawned with some future.
let scheduler = WithInfo(schedule);
// Create a task with the future and the scheduler.
let (runnable, task) = async_task::spawn(future, scheduler);

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

woken_while_running: bool

Indicates whether the task gets woken up while running.

It is set to true usually because the task has yielded itself to the scheduler.

Trait Implementations

impl Clone for ScheduleInfo

fn clone(&self) -> ScheduleInfo

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ScheduleInfo

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

Formats the value using the given formatter.

impl Copy for ScheduleInfo