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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/registry/src/github.com-1ecc6299db9ec823/tokio-1.28.2/src/time/sleep.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>sleep.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>::runtime::time::TimerEntry;
 <span class="kw">use </span><span class="kw">crate</span>::time::{error::Error, Duration, Instant};
 <span class="kw">use </span><span class="kw">crate</span>::util::trace;

 <span class="kw">use </span>pin_project_lite::pin_project;
 <span class="kw">use </span>std::future::Future;
 <span class="kw">use </span>std::panic::Location;
 <span class="kw">use </span>std::pin::Pin;
 <span class="kw">use </span>std::task::{<span class="self">self</span>, Poll};

 <span class="doccomment">/// Waits until `deadline` is reached.
 ///
 /// No work is performed while awaiting on the sleep future to complete. `Sleep`
 /// operates at millisecond granularity and should not be used for tasks that
 /// require high-resolution timers.
 ///
 /// To run something regularly on a schedule, see [`interval`].
 ///
 /// # Cancellation
 ///
 /// Canceling a sleep instance is done by dropping the returned future. No additional
 /// cleanup work is required.
 ///
 /// # Examples
 ///
 /// Wait 100ms and print &quot;100 ms have elapsed&quot;.
 ///
 /// ```
 /// use tokio::time::{sleep_until, Instant, Duration};
 ///
 /// #[tokio::main]
 /// async fn main() {
 ///     sleep_until(Instant::now() + Duration::from_millis(100)).await;
 ///     println!(&quot;100 ms have elapsed&quot;);
 /// }
 /// ```
 ///
 /// See the documentation for the [`Sleep`] type for more examples.
 ///
 /// # Panics
 ///
 /// This function panics if there is no current timer set.
 ///
 /// It can be triggered when [`Builder::enable_time`] or
 /// [`Builder::enable_all`] are not included in the builder.
 ///
 /// It can also panic whenever a timer is created outside of a
 /// Tokio runtime. That is why `rt.block_on(sleep(...))` will panic,
 /// since the function is executed outside of the runtime.
 /// Whereas `rt.block_on(async {sleep(...).await})` doesn&#39;t panic.
 /// And this is because wrapping the function on an async makes it lazy,
 /// and so gets executed inside the runtime successfully without
 /// panicking.
 ///
 /// [`Sleep`]: struct@crate::time::Sleep
 /// [`interval`]: crate::time::interval()
 /// [`Builder::enable_time`]: crate::runtime::Builder::enable_time
 /// [`Builder::enable_all`]: crate::runtime::Builder::enable_all
 </span><span class="comment">// Alias for old name in 0.x
 </span><span class="attribute">#[cfg_attr(docsrs, doc(alias = <span class="string">&quot;delay_until&quot;</span>))]
 #[track_caller]
 </span><span class="kw">pub fn </span>sleep_until(deadline: Instant) -&gt; Sleep {
     <span class="kw">return </span>Sleep::new_timeout(deadline, trace::caller_location());
 }

 <span class="doccomment">/// Waits until `duration` has elapsed.
 ///
 /// Equivalent to `sleep_until(Instant::now() + duration)`. An asynchronous
 /// analog to `std::thread::sleep`.
 ///
 /// No work is performed while awaiting on the sleep future to complete. `Sleep`
 /// operates at millisecond granularity and should not be used for tasks that
 /// require high-resolution timers. The implementation is platform specific,
 /// and some platforms (specifically Windows) will provide timers with a
 /// larger resolution than 1 ms.
 ///
 /// To run something regularly on a schedule, see [`interval`].
 ///
 /// The maximum duration for a sleep is 68719476734 milliseconds (approximately 2.2 years).
 ///
 /// # Cancellation
 ///
 /// Canceling a sleep instance is done by dropping the returned future. No additional
 /// cleanup work is required.
 ///
 /// # Examples
 ///
 /// Wait 100ms and print &quot;100 ms have elapsed&quot;.
 ///
 /// ```
 /// use tokio::time::{sleep, Duration};
 ///
 /// #[tokio::main]
 /// async fn main() {
 ///     sleep(Duration::from_millis(100)).await;
 ///     println!(&quot;100 ms have elapsed&quot;);
 /// }
 /// ```
 ///
 /// See the documentation for the [`Sleep`] type for more examples.
 ///
 /// # Panics
 ///
 /// This function panics if there is no current timer set.
 ///
 /// It can be triggered when [`Builder::enable_time`] or
 /// [`Builder::enable_all`] are not included in the builder.
 ///
 /// It can also panic whenever a timer is created outside of a
 /// Tokio runtime. That is why `rt.block_on(sleep(...))` will panic,
 /// since the function is executed outside of the runtime.
 /// Whereas `rt.block_on(async {sleep(...).await})` doesn&#39;t panic.
 /// And this is because wrapping the function on an async makes it lazy,
 /// and so gets executed inside the runtime successfully without
 /// panicking.
 ///
 /// [`Sleep`]: struct@crate::time::Sleep
 /// [`interval`]: crate::time::interval()
 /// [`Builder::enable_time`]: crate::runtime::Builder::enable_time
 /// [`Builder::enable_all`]: crate::runtime::Builder::enable_all
 </span><span class="comment">// Alias for old name in 0.x
 </span><span class="attribute">#[cfg_attr(docsrs, doc(alias = <span class="string">&quot;delay_for&quot;</span>))]
 #[cfg_attr(docsrs, doc(alias = <span class="string">&quot;wait&quot;</span>))]
 #[track_caller]
 </span><span class="kw">pub fn </span>sleep(duration: Duration) -&gt; Sleep {
     <span class="kw">let </span>location = trace::caller_location();

     <span class="kw">match </span>Instant::now().checked_add(duration) {
         <span class="prelude-val">Some</span>(deadline) =&gt; Sleep::new_timeout(deadline, location),
         <span class="prelude-val">None </span>=&gt; Sleep::new_timeout(Instant::far_future(), location),
     }
 }

 <span class="macro">pin_project! </span>{
     <span class="doccomment">/// Future returned by [`sleep`](sleep) and [`sleep_until`](sleep_until).
     ///
     /// This type does not implement the `Unpin` trait, which means that if you
     /// use it with [`select!`] or by calling `poll`, you have to pin it first.
     /// If you use it with `.await`, this does not apply.
     ///
     /// # Examples
     ///
     /// Wait 100ms and print &quot;100 ms have elapsed&quot;.
     ///
     /// ```
     /// use tokio::time::{sleep, Duration};
     ///
     /// #[tokio::main]
     /// async fn main() {
     ///     sleep(Duration::from_millis(100)).await;
     ///     println!(&quot;100 ms have elapsed&quot;);
     /// }
     /// ```
     ///
     /// Use with [`select!`]. Pinning the `Sleep` with [`tokio::pin!`] is
     /// necessary when the same `Sleep` is selected on multiple times.
     /// ```no_run
     /// use tokio::time::{self, Duration, Instant};
     ///
     /// #[tokio::main]
     /// async fn main() {
     ///     let sleep = time::sleep(Duration::from_millis(10));
     ///     tokio::pin!(sleep);
     ///
     ///     loop {
     ///         tokio::select! {
     ///             () = &amp;mut sleep =&gt; {
     ///                 println!(&quot;timer elapsed&quot;);
     ///                 sleep.as_mut().reset(Instant::now() + Duration::from_millis(50));
     ///             },
     ///         }
     ///     }
     /// }
     /// ```
     /// Use in a struct with boxing. By pinning the `Sleep` with a `Box`, the
     /// `HasSleep` struct implements `Unpin`, even though `Sleep` does not.
     /// ```
     /// use std::future::Future;
     /// use std::pin::Pin;
     /// use std::task::{Context, Poll};
     /// use tokio::time::Sleep;
     ///
     /// struct HasSleep {
     ///     sleep: Pin&lt;Box&lt;Sleep&gt;&gt;,
     /// }
     ///
     /// impl Future for HasSleep {
     ///     type Output = ();
     ///
     ///     fn poll(mut self: Pin&lt;&amp;mut Self&gt;, cx: &amp;mut Context&lt;&#39;_&gt;) -&gt; Poll&lt;()&gt; {
     ///         self.sleep.as_mut().poll(cx)
     ///     }
     /// }
     /// ```
     /// Use in a struct with pin projection. This method avoids the `Box`, but
     /// the `HasSleep` struct will not be `Unpin` as a consequence.
     /// ```
     /// use std::future::Future;
     /// use std::pin::Pin;
     /// use std::task::{Context, Poll};
     /// use tokio::time::Sleep;
     /// use pin_project_lite::pin_project;
     ///
     /// pin_project! {
     ///     struct HasSleep {
     ///         #[pin]
     ///         sleep: Sleep,
     ///     }
     /// }
     ///
     /// impl Future for HasSleep {
     ///     type Output = ();
     ///
     ///     fn poll(self: Pin&lt;&amp;mut Self&gt;, cx: &amp;mut Context&lt;&#39;_&gt;) -&gt; Poll&lt;()&gt; {
     ///         self.project().sleep.poll(cx)
     ///     }
     /// }
     /// ```
     ///
     /// [`select!`]: ../macro.select.html
     /// [`tokio::pin!`]: ../macro.pin.html
     </span><span class="comment">// Alias for old name in 0.2
     </span><span class="attribute">#[cfg_attr(docsrs, doc(alias = <span class="string">&quot;Delay&quot;</span>))]
     #[derive(Debug)]
     #[must_use = <span class="string">&quot;futures do nothing unless you `.await` or poll them&quot;</span>]
     </span><span class="kw">pub struct </span>Sleep {
         inner: Inner,

         <span class="comment">// The link between the `Sleep` instance and the timer that drives it.
         </span><span class="attribute">#[pin]
         </span>entry: TimerEntry,
     }
 }

 <span class="macro">cfg_trace! </span>{
     <span class="attribute">#[derive(Debug)]
     </span><span class="kw">struct </span>Inner {
         ctx: trace::AsyncOpTracingCtx,
     }
 }

 <span class="macro">cfg_not_trace! </span>{
     <span class="attribute">#[derive(Debug)]
     </span><span class="kw">struct </span>Inner {
     }
 }

 <span class="kw">impl </span>Sleep {
     <span class="attribute">#[cfg_attr(not(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>)), allow(unused_variables))]
     #[track_caller]
     </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>new_timeout(
         deadline: Instant,
         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; Sleep {
         <span class="kw">use </span><span class="kw">crate</span>::runtime::scheduler;

         <span class="kw">let </span>handle = scheduler::Handle::current();
         <span class="kw">let </span>entry = TimerEntry::new(<span class="kw-2">&amp;</span>handle, deadline);

         <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
         </span><span class="kw">let </span>inner = {
             <span class="kw">let </span>clock = handle.driver().clock();
             <span class="kw">let </span>handle = <span class="kw-2">&amp;</span>handle.driver().time();
             <span class="kw">let </span>time_source = handle.time_source();
             <span class="kw">let </span>deadline_tick = time_source.deadline_to_tick(deadline);
             <span class="kw">let </span>duration = deadline_tick.saturating_sub(time_source.now(clock));

             <span class="kw">let </span>location = location.expect(<span class="string">&quot;should have location if tracing&quot;</span>);
             <span class="kw">let </span>resource_span = <span class="macro">tracing::trace_span!</span>(
                 <span class="string">&quot;runtime.resource&quot;</span>,
                 concrete_type = <span class="string">&quot;Sleep&quot;</span>,
                 kind = <span class="string">&quot;timer&quot;</span>,
                 loc.file = location.file(),
                 loc.line = location.line(),
                 loc.col = location.column(),
             );

             <span class="kw">let </span>async_op_span = resource_span.in_scope(|| {
                 <span class="macro">tracing::trace!</span>(
                     target: <span class="string">&quot;runtime::resource::state_update&quot;</span>,
                     duration = duration,
                     duration.unit = <span class="string">&quot;ms&quot;</span>,
                     duration.op = <span class="string">&quot;override&quot;</span>,
                 );

                 <span class="macro">tracing::trace_span!</span>(<span class="string">&quot;runtime.resource.async_op&quot;</span>, source = <span class="string">&quot;Sleep::new_timeout&quot;</span>)
             });

             <span class="kw">let </span>async_op_poll_span =
                 async_op_span.in_scope(|| <span class="macro">tracing::trace_span!</span>(<span class="string">&quot;runtime.resource.async_op.poll&quot;</span>));

             <span class="kw">let </span>ctx = trace::AsyncOpTracingCtx {
                 async_op_span,
                 async_op_poll_span,
                 resource_span,
             };

             Inner { ctx }
         };

         <span class="attribute">#[cfg(not(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>)))]
         </span><span class="kw">let </span>inner = Inner {};

         Sleep { inner, entry }
     }

     <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>far_future(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; Sleep {
         <span class="self">Self</span>::new_timeout(Instant::far_future(), location)
     }

     <span class="doccomment">/// Returns the instant at which the future will complete.
     </span><span class="kw">pub fn </span>deadline(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; Instant {
         <span class="self">self</span>.entry.deadline()
     }

     <span class="doccomment">/// Returns `true` if `Sleep` has elapsed.
     ///
     /// A `Sleep` instance is elapsed when the requested duration has elapsed.
     </span><span class="kw">pub fn </span>is_elapsed(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; bool {
         <span class="self">self</span>.entry.is_elapsed()
     }

     <span class="doccomment">/// Resets the `Sleep` instance to a new deadline.
     ///
     /// Calling this function allows changing the instant at which the `Sleep`
     /// future completes without having to create new associated state.
     ///
     /// This function can be called both before and after the future has
     /// completed.
     ///
     /// To call this method, you will usually combine the call with
     /// [`Pin::as_mut`], which lets you call the method without consuming the
     /// `Sleep` itself.
     ///
     /// # Example
     ///
     /// ```
     /// use tokio::time::{Duration, Instant};
     ///
     /// # #[tokio::main(flavor = &quot;current_thread&quot;)]
     /// # async fn main() {
     /// let sleep = tokio::time::sleep(Duration::from_millis(10));
     /// tokio::pin!(sleep);
     ///
     /// sleep.as_mut().reset(Instant::now() + Duration::from_millis(20));
     /// # }
     /// ```
     ///
     /// See also the top-level examples.
     ///
     /// [`Pin::as_mut`]: fn@std::pin::Pin::as_mut
     </span><span class="kw">pub fn </span>reset(<span class="self">self</span>: Pin&lt;<span class="kw-2">&amp;mut </span><span class="self">Self</span>&gt;, deadline: Instant) {
         <span class="self">self</span>.reset_inner(deadline)
     }

     <span class="doccomment">/// Resets the `Sleep` instance to a new deadline without reregistering it
     /// to be woken up.
     ///
     /// Calling this function allows changing the instant at which the `Sleep`
     /// future completes without having to create new associated state and
     /// without having it registered. This is required in e.g. the
     /// [crate::time::Interval] where we want to reset the internal [Sleep]
     /// without having it wake up the last task that polled it.
     </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>reset_without_reregister(<span class="self">self</span>: Pin&lt;<span class="kw-2">&amp;mut </span><span class="self">Self</span>&gt;, deadline: Instant) {
         <span class="kw">let </span><span class="kw-2">mut </span>me = <span class="self">self</span>.project();
         me.entry.as_mut().reset(deadline, <span class="bool-val">false</span>);
     }

     <span class="kw">fn </span>reset_inner(<span class="self">self</span>: Pin&lt;<span class="kw-2">&amp;mut </span><span class="self">Self</span>&gt;, deadline: Instant) {
         <span class="kw">let </span><span class="kw-2">mut </span>me = <span class="self">self</span>.project();
         me.entry.as_mut().reset(deadline, <span class="bool-val">true</span>);

         <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
         </span>{
             <span class="kw">let </span>_resource_enter = me.inner.ctx.resource_span.enter();
             me.inner.ctx.async_op_span =
                 <span class="macro">tracing::trace_span!</span>(<span class="string">&quot;runtime.resource.async_op&quot;</span>, source = <span class="string">&quot;Sleep::reset&quot;</span>);
             <span class="kw">let </span>_async_op_enter = me.inner.ctx.async_op_span.enter();

             me.inner.ctx.async_op_poll_span =
                 <span class="macro">tracing::trace_span!</span>(<span class="string">&quot;runtime.resource.async_op.poll&quot;</span>);

             <span class="kw">let </span>duration = {
                 <span class="kw">let </span>clock = me.entry.clock();
                 <span class="kw">let </span>time_source = me.entry.driver().time_source();
                 <span class="kw">let </span>now = time_source.now(clock);
                 <span class="kw">let </span>deadline_tick = time_source.deadline_to_tick(deadline);
                 deadline_tick.saturating_sub(now)
             };

             <span class="macro">tracing::trace!</span>(
                 target: <span class="string">&quot;runtime::resource::state_update&quot;</span>,
                 duration = duration,
                 duration.unit = <span class="string">&quot;ms&quot;</span>,
                 duration.op = <span class="string">&quot;override&quot;</span>,
             );
         }
     }

     <span class="kw">fn </span>poll_elapsed(<span class="self">self</span>: Pin&lt;<span class="kw-2">&amp;mut </span><span class="self">Self</span>&gt;, cx: <span class="kw-2">&amp;mut </span>task::Context&lt;<span class="lifetime">&#39;_</span>&gt;) -&gt; Poll&lt;<span class="prelude-ty">Result</span>&lt;(), Error&gt;&gt; {
         <span class="kw">let </span>me = <span class="self">self</span>.project();

         <span class="comment">// Keep track of task budget
         </span><span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
         </span><span class="kw">let </span>coop = <span class="macro">ready!</span>(<span class="macro">trace_poll_op!</span>(
             <span class="string">&quot;poll_elapsed&quot;</span>,
             <span class="kw">crate</span>::runtime::coop::poll_proceed(cx),
         ));

         <span class="attribute">#[cfg(any(not(tokio_unstable), not(feature = <span class="string">&quot;tracing&quot;</span>)))]
         </span><span class="kw">let </span>coop = <span class="macro">ready!</span>(<span class="kw">crate</span>::runtime::coop::poll_proceed(cx));

         <span class="kw">let </span>result = me.entry.poll_elapsed(cx).map(<span class="kw">move </span>|r| {
             coop.made_progress();
             r
         });

         <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
         </span><span class="kw">return </span><span class="macro">trace_poll_op!</span>(<span class="string">&quot;poll_elapsed&quot;</span>, result);

         <span class="attribute">#[cfg(any(not(tokio_unstable), not(feature = <span class="string">&quot;tracing&quot;</span>)))]
         </span><span class="kw">return </span>result;
     }
 }

 <span class="kw">impl </span>Future <span class="kw">for </span>Sleep {
     <span class="kw">type </span>Output = ();

     <span class="comment">// `poll_elapsed` can return an error in two cases:
     //
     // - AtCapacity: this is a pathological case where far too many
     //   sleep instances have been scheduled.
     // - Shutdown: No timer has been setup, which is a mis-use error.
     //
     // Both cases are extremely rare, and pretty accurately fit into
     // &quot;logic errors&quot;, so we just panic in this case. A user couldn&#39;t
     // really do much better if we passed the error onwards.
     </span><span class="kw">fn </span>poll(<span class="kw-2">mut </span><span class="self">self</span>: Pin&lt;<span class="kw-2">&amp;mut </span><span class="self">Self</span>&gt;, cx: <span class="kw-2">&amp;mut </span>task::Context&lt;<span class="lifetime">&#39;_</span>&gt;) -&gt; Poll&lt;<span class="self">Self</span>::Output&gt; {
         <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
         </span><span class="kw">let </span>_res_span = <span class="self">self</span>.inner.ctx.resource_span.clone().entered();
         <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
         </span><span class="kw">let </span>_ao_span = <span class="self">self</span>.inner.ctx.async_op_span.clone().entered();
         <span class="attribute">#[cfg(all(tokio_unstable, feature = <span class="string">&quot;tracing&quot;</span>))]
         </span><span class="kw">let </span>_ao_poll_span = <span class="self">self</span>.inner.ctx.async_op_poll_span.clone().entered();
         <span class="kw">match </span><span class="macro">ready!</span>(<span class="self">self</span>.as_mut().poll_elapsed(cx)) {
             <span class="prelude-val">Ok</span>(()) =&gt; Poll::Ready(()),
             <span class="prelude-val">Err</span>(e) =&gt; <span class="macro">panic!</span>(<span class="string">&quot;timer error: {}&quot;</span>, e),
         }
     }
 }
 </code></pre></div>
 </section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="tokio" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html>