Struct tokio::time::Interval

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pub struct Interval { /* private fields */ }

Available on crate feature time only.

Expand description

Interval returned by interval and interval_at.

This type allows you to wait on a sequence of instants with a certain duration between each instant. Unlike calling sleep in a loop, this lets you count the time spent between the calls to sleep as well.

An Interval can be turned into a Stream with IntervalStream.

Implementations§

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impl Interval

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pub async fn tick(&mut self) -> Instant

Completes when the next instant in the interval has been reached.

Cancel safety

This method is cancellation safe. If tick is used as the branch in a tokio::select! and another branch completes first, then no tick has been consumed.

Examples

use tokio::time;

use std::time::Duration;

#[tokio::main]
async fn main() {
    let mut interval = time::interval(Duration::from_millis(10));

    interval.tick().await;
    // approximately 0ms have elapsed. The first tick completes immediately.
    interval.tick().await;
    interval.tick().await;

    // approximately 20ms have elapsed.
}

source

pub fn poll_tick(&mut self, cx: &mut Context<'_>) -> Poll<Instant>

Polls for the next instant in the interval to be reached.

This method can return the following values:

Poll::Pending if the next instant has not yet been reached.
Poll::Ready(instant) if the next instant has been reached.

When this method returns Poll::Pending, the current task is scheduled to receive a wakeup when the instant has elapsed. Note that on multiple calls to poll_tick, only the Waker from the Context passed to the most recent call is scheduled to receive a wakeup.

source

pub fn reset(&mut self)

Resets the interval to complete one period after the current time.

This method ignores MissedTickBehavior strategy.

Examples

use tokio::time;

use std::time::Duration;

#[tokio::main]
async fn main() {
    let mut interval = time::interval(Duration::from_millis(100));

    interval.tick().await;

    time::sleep(Duration::from_millis(50)).await;
    interval.reset();

    interval.tick().await;
    interval.tick().await;

    // approximately 250ms have elapsed.
}