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 <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `/root/.cargo/git/checkouts/tokio-377c595163f99a10/dfe252d/tokio/src/time/interval.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>interval.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../../normalize.css"><link rel="stylesheet" href="../../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../../ayu.css" disabled><link rel="stylesheet" href="../../../dark.css" disabled><link rel="stylesheet" href="../../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../../storage.js"></script><script defer src="../../../source-script.js"></script><script defer src="../../../source-files.js"></script><script defer src="../../../main.js"></script><noscript><link rel="stylesheet" href="../../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../../favicon.svg"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../../tokio/index.html"><div class="logo-container"><img class="rust-logo" src="../../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../../tokio/index.html"><img class="rust-logo" src="../../../rust-logo.svg" alt="logo"></a><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span>
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 </pre><pre class="rust"><code><span class="kw">use </span><span class="kw">crate</span>::future::poll_fn;
 <span class="kw">use </span><span class="kw">crate</span>::time::{sleep_until, Duration, Instant, Sleep};
 <span class="kw">use </span><span class="kw">crate</span>::util::trace;

 <span class="kw">use </span>std::panic::Location;
 <span class="kw">use </span>std::pin::Pin;
 <span class="kw">use </span>std::task::{Context, Poll};
 <span class="kw">use </span>std::{convert::TryInto, future::Future};

 <span class="doccomment">/// Creates new [`Interval`] that yields with interval of `period`. The first
 /// tick completes immediately. The default [`MissedTickBehavior`] is
 /// [`Burst`](MissedTickBehavior::Burst), but this can be configured
 /// by calling [`set_missed_tick_behavior`](Interval::set_missed_tick_behavior).
 ///
 /// An interval will tick indefinitely. At any time, the [`Interval`] value can
 /// be dropped. This cancels the interval.
 ///
 /// This function is equivalent to
 /// [`interval_at(Instant::now(), period)`](interval_at).
 ///
 /// # Panics
 ///
 /// This function panics if `period` is zero.
 ///
 /// # Examples
 ///
 /// ```
 /// use tokio::time::{self, Duration};
 ///
 /// #[tokio::main]
 /// async fn main() {
 ///     let mut interval = time::interval(Duration::from_millis(10));
 ///
 ///     interval.tick().await; // ticks immediately
 ///     interval.tick().await; // ticks after 10ms
 ///     interval.tick().await; // ticks after 10ms
 ///
 ///     // approximately 20ms have elapsed.
 /// }
 /// ```
 ///
 /// A simple example using `interval` to execute a task every two seconds.
 ///
 /// The difference between `interval` and [`sleep`] is that an [`Interval`]
 /// measures the time since the last tick, which means that [`.tick().await`]
 /// may wait for a shorter time than the duration specified for the interval
 /// if some time has passed between calls to [`.tick().await`].
 ///
 /// If the tick in the example below was replaced with [`sleep`], the task
 /// would only be executed once every three seconds, and not every two
 /// seconds.
 ///
 /// ```
 /// use tokio::time;
 ///
 /// async fn task_that_takes_a_second() {
 ///     println!(&quot;hello&quot;);
 ///     time::sleep(time::Duration::from_secs(1)).await
 /// }
 ///
 /// #[tokio::main]
 /// async fn main() {
 ///     let mut interval = time::interval(time::Duration::from_secs(2));
 ///     for _i in 0..5 {
 ///         interval.tick().await;
 ///         task_that_takes_a_second().await;
 ///     }
 /// }
 /// ```
 ///
 /// [`sleep`]: crate::time::sleep()
 /// [`.tick().await`]: Interval::tick
 </span><span class="attribute">#[track_caller]
 </span><span class="kw">pub fn </span>interval(period: Duration) -&gt; Interval {
     <span class="macro">assert!</span>(period &gt; Duration::new(<span class="number">0</span>, <span class="number">0</span>), <span class="string">&quot;`period` must be non-zero.&quot;</span>);
     internal_interval_at(Instant::now(), period, trace::caller_location())
 }

 <span class="doccomment">/// Creates new [`Interval`] that yields with interval of `period` with the
 /// first tick completing at `start`. The default [`MissedTickBehavior`] is
 /// [`Burst`](MissedTickBehavior::Burst), but this can be configured
 /// by calling [`set_missed_tick_behavior`](Interval::set_missed_tick_behavior).
 ///
 /// An interval will tick indefinitely. At any time, the [`Interval`] value can
 /// be dropped. This cancels the interval.
 ///
 /// # Panics
 ///
 /// This function panics if `period` is zero.
 ///
 /// # Examples
 ///
 /// ```
 /// use tokio::time::{interval_at, Duration, Instant};
 ///
 /// #[tokio::main]
 /// async fn main() {
 ///     let start = Instant::now() + Duration::from_millis(50);
 ///     let mut interval = interval_at(start, Duration::from_millis(10));
 ///
 ///     interval.tick().await; // ticks after 50ms
 ///     interval.tick().await; // ticks after 10ms
 ///     interval.tick().await; // ticks after 10ms
 ///
 ///     // approximately 70ms have elapsed.
 /// }
 /// ```
 </span><span class="attribute">#[track_caller]
 </span><span class="kw">pub fn </span>interval_at(start: Instant, period: Duration) -&gt; Interval {
     <span class="macro">assert!</span>(period &gt; Duration::new(<span class="number">0</span>, <span class="number">0</span>), <span class="string">&quot;`period` must be non-zero.&quot;</span>);
     internal_interval_at(start, period, trace::caller_location())
 }

 <span class="attribute">#[cfg_attr(not(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>)), allow(unused_variables))]
 </span><span class="kw">fn </span>internal_interval_at(
     start: Instant,
     period: Duration,
     location: <span class="prelude-ty">Option</span>&lt;<span class="kw-2">&amp;</span><span class="lifetime">&#39;static </span>Location&lt;<span class="lifetime">&#39;static</span>&gt;&gt;,
 ) -&gt; Interval {
     <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
     </span><span class="kw">let </span>resource_span = {
         <span class="kw">let </span>location = location.expect(<span class="string">&quot;should have location if tracing&quot;</span>);

         <span class="macro">tracing::trace_span!</span>(
             <span class="string">&quot;runtime.resource&quot;</span>,
             concrete_type = <span class="string">&quot;Interval&quot;</span>,
             kind = <span class="string">&quot;timer&quot;</span>,
             loc.file = location.file(),
             loc.line = location.line(),
             loc.col = location.column(),
         )
     };

     <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
     </span><span class="kw">let </span>delay = resource_span.in_scope(|| Box::pin(sleep_until(start)));

     <span class="attribute">#[cfg(not(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>)))]
     </span><span class="kw">let </span>delay = Box::pin(sleep_until(start));

     Interval {
         delay,
         period,
         missed_tick_behavior: Default::default(),
         <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
         </span>resource_span,
     }
 }

 <span class="doccomment">/// Defines the behavior of an [`Interval`] when it misses a tick.
 ///
 /// Sometimes, an [`Interval`]&#39;s tick is missed. For example, consider the
 /// following:
 ///
 /// ```
 /// use tokio::time::{self, Duration};
 /// # async fn task_that_takes_one_to_three_millis() {}
 ///
 /// #[tokio::main]
 /// async fn main() {
 ///     // ticks every 2 milliseconds
 ///     let mut interval = time::interval(Duration::from_millis(2));
 ///     for _ in 0..5 {
 ///         interval.tick().await;
 ///         // if this takes more than 2 milliseconds, a tick will be delayed
 ///         task_that_takes_one_to_three_millis().await;
 ///     }
 /// }
 /// ```
 ///
 /// Generally, a tick is missed if too much time is spent without calling
 /// [`Interval::tick()`].
 ///
 /// By default, when a tick is missed, [`Interval`] fires ticks as quickly as it
 /// can until it is &quot;caught up&quot; in time to where it should be.
 /// `MissedTickBehavior` can be used to specify a different behavior for
 /// [`Interval`] to exhibit. Each variant represents a different strategy.
 ///
 /// Note that because the executor cannot guarantee exact precision with timers,
 /// these strategies will only apply when the delay is greater than 5
 /// milliseconds.
 </span><span class="attribute">#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 </span><span class="kw">pub enum </span>MissedTickBehavior {
     <span class="doccomment">/// Ticks as fast as possible until caught up.
     ///
     /// When this strategy is used, [`Interval`] schedules ticks &quot;normally&quot; (the
     /// same as it would have if the ticks hadn&#39;t been delayed), which results
     /// in it firing ticks as fast as possible until it is caught up in time to
     /// where it should be. Unlike [`Delay`] and [`Skip`], the ticks yielded
     /// when `Burst` is used (the [`Instant`]s that [`tick`](Interval::tick)
     /// yields) aren&#39;t different than they would have been if a tick had not
     /// been missed. Like [`Skip`], and unlike [`Delay`], the ticks may be
     /// shortened.
     ///
     /// This looks something like this:
     /// ```text
     /// Expected ticks: |     1     |     2     |     3     |     4     |     5     |     6     |
     /// Actual ticks:   | work -----|          delay          | work | work | work -| work -----|
     /// ```
     ///
     /// In code:
     ///
     /// ```
     /// use tokio::time::{interval, Duration};
     /// # async fn task_that_takes_200_millis() {}
     ///
     /// # #[tokio::main(flavor = &quot;current_thread&quot;)]
     /// # async fn main() {
     /// let mut interval = interval(Duration::from_millis(50));
     ///
     /// // First tick resolves immediately after creation
     /// interval.tick().await;
     ///
     /// task_that_takes_200_millis().await;
     /// // The `Interval` has missed a tick
     ///
     /// // Since we have exceeded our timeout, this will resolve immediately
     /// interval.tick().await;
     ///
     /// // Since we are more than 100ms after the start of `interval`, this will
     /// // also resolve immediately.
     /// interval.tick().await;
     ///
     /// // Also resolves immediately, because it was supposed to resolve at
     /// // 150ms after the start of `interval`
     /// interval.tick().await;
     ///
     /// // Resolves immediately
     /// interval.tick().await;
     ///
     /// // Since we have gotten to 200ms after the start of `interval`, this
     /// // will resolve after 50ms
     /// interval.tick().await;
     /// # }
     /// ```
     ///
     /// This is the default behavior when [`Interval`] is created with
     /// [`interval`] and [`interval_at`].
     ///
     /// [`Delay`]: MissedTickBehavior::Delay
     /// [`Skip`]: MissedTickBehavior::Skip
     </span>Burst,

     <span class="doccomment">/// Tick at multiples of `period` from when [`tick`] was called, rather than
     /// from `start`.
     ///
     /// When this strategy is used and [`Interval`] has missed a tick, instead
     /// of scheduling ticks to fire at multiples of `period` from `start` (the
     /// time when the first tick was fired), it schedules all future ticks to
     /// happen at a regular `period` from the point when [`tick`] was called.
     /// Unlike [`Burst`] and [`Skip`], ticks are not shortened, and they aren&#39;t
     /// guaranteed to happen at a multiple of `period` from `start` any longer.
     ///
     /// This looks something like this:
     /// ```text
     /// Expected ticks: |     1     |     2     |     3     |     4     |     5     |     6     |
     /// Actual ticks:   | work -----|          delay          | work -----| work -----| work -----|
     /// ```
     ///
     /// In code:
     ///
     /// ```
     /// use tokio::time::{interval, Duration, MissedTickBehavior};
     /// # async fn task_that_takes_more_than_50_millis() {}
     ///
     /// # #[tokio::main(flavor = &quot;current_thread&quot;)]
     /// # async fn main() {
     /// let mut interval = interval(Duration::from_millis(50));
     /// interval.set_missed_tick_behavior(MissedTickBehavior::Delay);
     ///
     /// task_that_takes_more_than_50_millis().await;
     /// // The `Interval` has missed a tick
     ///
     /// // Since we have exceeded our timeout, this will resolve immediately
     /// interval.tick().await;
     ///
     /// // But this one, rather than also resolving immediately, as might happen
     /// // with the `Burst` or `Skip` behaviors, will not resolve until
     /// // 50ms after the call to `tick` up above. That is, in `tick`, when we
     /// // recognize that we missed a tick, we schedule the next tick to happen
     /// // 50ms (or whatever the `period` is) from right then, not from when
     /// // were *supposed* to tick
     /// interval.tick().await;
     /// # }
     /// ```
     ///
     /// [`Burst`]: MissedTickBehavior::Burst
     /// [`Skip`]: MissedTickBehavior::Skip
     /// [`tick`]: Interval::tick
     </span>Delay,

     <span class="doccomment">/// Skips missed ticks and tick on the next multiple of `period` from
     /// `start`.
     ///
     /// When this strategy is used, [`Interval`] schedules the next tick to fire
     /// at the next-closest tick that is a multiple of `period` away from
     /// `start` (the point where [`Interval`] first ticked). Like [`Burst`], all
     /// ticks remain multiples of `period` away from `start`, but unlike
     /// [`Burst`], the ticks may not be *one* multiple of `period` away from the
     /// last tick. Like [`Delay`], the ticks are no longer the same as they
     /// would have been if ticks had not been missed, but unlike [`Delay`], and
     /// like [`Burst`], the ticks may be shortened to be less than one `period`
     /// away from each other.
     ///
     /// This looks something like this:
     /// ```text
     /// Expected ticks: |     1     |     2     |     3     |     4     |     5     |     6     |
     /// Actual ticks:   | work -----|          delay          | work ---| work -----| work -----|
     /// ```
     ///
     /// In code:
     ///
     /// ```
     /// use tokio::time::{interval, Duration, MissedTickBehavior};
     /// # async fn task_that_takes_75_millis() {}
     ///
     /// # #[tokio::main(flavor = &quot;current_thread&quot;)]
     /// # async fn main() {
     /// let mut interval = interval(Duration::from_millis(50));
     /// interval.set_missed_tick_behavior(MissedTickBehavior::Skip);
     ///
     /// task_that_takes_75_millis().await;
     /// // The `Interval` has missed a tick
     ///
     /// // Since we have exceeded our timeout, this will resolve immediately
     /// interval.tick().await;
     ///
     /// // This one will resolve after 25ms, 100ms after the start of
     /// // `interval`, which is the closest multiple of `period` from the start
     /// // of `interval` after the call to `tick` up above.
     /// interval.tick().await;
     /// # }
     /// ```
     ///
     /// [`Burst`]: MissedTickBehavior::Burst
     /// [`Delay`]: MissedTickBehavior::Delay
     </span>Skip,
 }

 <span class="kw">impl </span>MissedTickBehavior {
     <span class="doccomment">/// If a tick is missed, this method is called to determine when the next tick should happen.
     </span><span class="kw">fn </span>next_timeout(<span class="kw-2">&amp;</span><span class="self">self</span>, timeout: Instant, now: Instant, period: Duration) -&gt; Instant {
         <span class="kw">match </span><span class="self">self </span>{
             <span class="self">Self</span>::Burst =&gt; timeout + period,
             <span class="self">Self</span>::Delay =&gt; now + period,
             <span class="self">Self</span>::Skip =&gt; {
                 now + period
                     - Duration::from_nanos(
                         ((now - timeout).as_nanos() % period.as_nanos())
                             .try_into()
                             <span class="comment">// This operation is practically guaranteed not to
                             // fail, as in order for it to fail, `period` would
                             // have to be longer than `now - timeout`, and both
                             // would have to be longer than 584 years.
                             //
                             // If it did fail, there&#39;s not a good way to pass
                             // the error along to the user, so we just panic.
                             </span>.expect(
                                 <span class="string">&quot;too much time has elapsed since the interval was supposed to tick&quot;</span>,
                             ),
                     )
             }
         }
     }
 }

 <span class="kw">impl </span>Default <span class="kw">for </span>MissedTickBehavior {
     <span class="doccomment">/// Returns [`MissedTickBehavior::Burst`].
     ///
     /// For most usecases, the [`Burst`] strategy is what is desired.
     /// Additionally, to preserve backwards compatibility, the [`Burst`]
     /// strategy must be the default. For these reasons,
     /// [`MissedTickBehavior::Burst`] is the default for [`MissedTickBehavior`].
     /// See [`Burst`] for more details.
     ///
     /// [`Burst`]: MissedTickBehavior::Burst
     </span><span class="kw">fn </span>default() -&gt; <span class="self">Self </span>{
         <span class="self">Self</span>::Burst
     }
 }

 <span class="doccomment">/// 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`].
 ///
 /// [`IntervalStream`]: https://docs.rs/tokio-stream/latest/tokio_stream/wrappers/struct.IntervalStream.html
 /// [`sleep`]: crate::time::sleep
 </span><span class="attribute">#[derive(Debug)]
 </span><span class="kw">pub struct </span>Interval {
     <span class="doccomment">/// Future that completes the next time the `Interval` yields a value.
     </span>delay: Pin&lt;Box&lt;Sleep&gt;&gt;,

     <span class="doccomment">/// The duration between values yielded by `Interval`.
     </span>period: Duration,

     <span class="doccomment">/// The strategy `Interval` should use when a tick is missed.
     </span>missed_tick_behavior: MissedTickBehavior,

     <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
     </span>resource_span: tracing::Span,
 }

 <span class="kw">impl </span>Interval {
     <span class="doccomment">/// 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.
     /// }
     /// ```
     </span><span class="kw">pub async fn </span>tick(<span class="kw-2">&amp;mut </span><span class="self">self</span>) -&gt; Instant {
         <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
         </span><span class="kw">let </span>resource_span = <span class="self">self</span>.resource_span.clone();
         <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
         </span><span class="kw">let </span>instant = trace::async_op(
             || poll_fn(|cx| <span class="self">self</span>.poll_tick(cx)),
             resource_span,
             <span class="string">&quot;Interval::tick&quot;</span>,
             <span class="string">&quot;poll_tick&quot;</span>,
             <span class="bool-val">false</span>,
         );
         <span class="attribute">#[cfg(not(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>)))]
         </span><span class="kw">let </span>instant = poll_fn(|cx| <span class="self">self</span>.poll_tick(cx));

         instant.<span class="kw">await
     </span>}

     <span class="doccomment">/// 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`](std::task::Waker) from the
     /// [`Context`] passed to the most recent call is scheduled to receive a
     /// wakeup.
     </span><span class="kw">pub fn </span>poll_tick(<span class="kw-2">&amp;mut </span><span class="self">self</span>, cx: <span class="kw-2">&amp;mut </span>Context&lt;<span class="lifetime">&#39;_</span>&gt;) -&gt; Poll&lt;Instant&gt; {
         <span class="comment">// Wait for the delay to be done
         </span><span class="macro">ready!</span>(Pin::new(<span class="kw-2">&amp;mut </span><span class="self">self</span>.delay).poll(cx));

         <span class="comment">// Get the time when we were scheduled to tick
         </span><span class="kw">let </span>timeout = <span class="self">self</span>.delay.deadline();

         <span class="kw">let </span>now = Instant::now();

         <span class="comment">// If a tick was not missed, and thus we are being called before the
         // next tick is due, just schedule the next tick normally, one `period`
         // after `timeout`
         //
         // However, if a tick took excessively long and we are now behind,
         // schedule the next tick according to how the user specified with
         // `MissedTickBehavior`
         </span><span class="kw">let </span>next = <span class="kw">if </span>now &gt; timeout + Duration::from_millis(<span class="number">5</span>) {
             <span class="self">self</span>.missed_tick_behavior
                 .next_timeout(timeout, now, <span class="self">self</span>.period)
         } <span class="kw">else </span>{
             timeout + <span class="self">self</span>.period
         };

         <span class="self">self</span>.delay.as_mut().reset(next);

         <span class="comment">// Return the time when we were scheduled to tick
         </span>Poll::Ready(timeout)
     }

     <span class="doccomment">/// 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.
     /// }
     /// ```
     </span><span class="kw">pub fn </span>reset(<span class="kw-2">&amp;mut </span><span class="self">self</span>) {
         <span class="self">self</span>.delay.as_mut().reset(Instant::now() + <span class="self">self</span>.period);
     }

     <span class="doccomment">/// Returns the [`MissedTickBehavior`] strategy currently being used.
     </span><span class="kw">pub fn </span>missed_tick_behavior(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; MissedTickBehavior {
         <span class="self">self</span>.missed_tick_behavior
     }

     <span class="doccomment">/// Sets the [`MissedTickBehavior`] strategy that should be used.
     </span><span class="kw">pub fn </span>set_missed_tick_behavior(<span class="kw-2">&amp;mut </span><span class="self">self</span>, behavior: MissedTickBehavior) {
         <span class="self">self</span>.missed_tick_behavior = behavior;
     }

     <span class="doccomment">/// Returns the period of the interval.
     </span><span class="kw">pub fn </span>period(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; Duration {
         <span class="self">self</span>.period
     }
 }
 </code></pre></div>
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