| <!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="A [`Waker`] that is only valid for a given lifetime."><meta name="keywords" content="rust, rustlang, rust-lang, WakerRef"><title>WakerRef in futures_task - Rust</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" 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class="logo-container"><img class="rust-logo" src="../rust-logo.svg" alt="logo"></div></a><h2></h2></nav><nav class="sidebar"><a class="sidebar-logo" href="../futures_task/index.html"><div class="logo-container"><img class="rust-logo" src="../rust-logo.svg" alt="logo"></div></a><h2 class="location"><a href="#">WakerRef</a></h2><div class="sidebar-elems"><section><h3><a href="#implementations">Methods</a></h3><ul class="block"><li><a href="#method.new">new</a></li><li><a href="#method.new_unowned">new_unowned</a></li></ul><h3><a href="#deref-methods-Waker">Methods from Deref<Target=Waker></a></h3><ul class="block"><li><a href="#method.as_raw">as_raw</a></li><li><a href="#method.wake_by_ref">wake_by_ref</a></li><li><a href="#method.will_wake">will_wake</a></li></ul><h3><a href="#trait-implementations">Trait Implementations</a></h3><ul class="block"><li><a href="#impl-Debug-for-WakerRef%3C%27a%3E">Debug</a></li><li><a href="#impl-Deref-for-WakerRef%3C%27_%3E">Deref</a></li></ul><h3><a href="#synthetic-implementations">Auto Trait Implementations</a></h3><ul class="block"><li><a href="#impl-RefUnwindSafe-for-WakerRef%3C%27a%3E">RefUnwindSafe</a></li><li><a href="#impl-Send-for-WakerRef%3C%27a%3E">Send</a></li><li><a href="#impl-Sync-for-WakerRef%3C%27a%3E">Sync</a></li><li><a href="#impl-Unpin-for-WakerRef%3C%27a%3E">Unpin</a></li><li><a href="#impl-UnwindSafe-for-WakerRef%3C%27a%3E">UnwindSafe</a></li></ul><h3><a href="#blanket-implementations">Blanket Implementations</a></h3><ul class="block"><li><a href="#impl-Any-for-WakerRef%3C%27a%3E">Any</a></li><li><a href="#impl-Borrow%3CT%3E-for-WakerRef%3C%27a%3E">Borrow<T></a></li><li><a href="#impl-BorrowMut%3CT%3E-for-WakerRef%3C%27a%3E">BorrowMut<T></a></li><li><a href="#impl-From%3CT%3E-for-WakerRef%3C%27a%3E">From<T></a></li><li><a href="#impl-Into%3CU%3E-for-WakerRef%3C%27a%3E">Into<U></a></li><li><a href="#impl-TryFrom%3CU%3E-for-WakerRef%3C%27a%3E">TryFrom<U></a></li><li><a href="#impl-TryInto%3CU%3E-for-WakerRef%3C%27a%3E">TryInto<U></a></li></ul></section><h2><a href="index.html">In futures_task</a></h2></div></nav><main><div class="width-limiter"><nav class="sub"><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="main-heading"><h1 class="fqn">Struct <a href="index.html">futures_task</a>::<wbr><a class="struct" href="#">WakerRef</a><button id="copy-path" onclick="copy_path(this)" title="Copy item path to clipboard"><img src="../clipboard.svg" width="19" height="18" alt="Copy item path"></button></h1><span class="out-of-band"><a class="srclink" href="../src/futures_task/waker_ref.rs.html#14-17">source</a> · <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class="inner">−</span>]</a></span></div><div class="item-decl"><pre class="rust struct"><code>pub struct WakerRef<'a> { /* private fields */ }</code></pre></div><details class="rustdoc-toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>A [<code>Waker</code>] that is only valid for a given lifetime.</p> |
| <p>Note: this type implements <a href="std::ops::Deref"><code>Deref<Target = Waker></code></a>, |
| so it can be used to get a <code>&Waker</code>.</p> |
| </div></details><h2 id="implementations" class="small-section-header">Implementations<a href="#implementations" class="anchor"></a></h2><div id="implementations-list"><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-WakerRef%3C%27a%3E" class="impl has-srclink"><a class="srclink rightside" href="../src/futures_task/waker_ref.rs.html#19-39">source</a><a href="#impl-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<'a> <a class="struct" href="struct.WakerRef.html" title="struct futures_task::WakerRef">WakerRef</a><'a></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.new" class="method has-srclink"><a class="srclink rightside" href="../src/futures_task/waker_ref.rs.html#22-27">source</a><h4 class="code-header">pub fn <a href="#method.new" class="fnname">new</a>(waker: &'a Waker) -> Self</h4></section></summary><div class="docblock"><p>Create a new <a href="struct.WakerRef.html" title="WakerRef"><code>WakerRef</code></a> from a [<code>Waker</code>] reference.</p> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.new_unowned" class="method has-srclink"><a class="srclink rightside" href="../src/futures_task/waker_ref.rs.html#36-38">source</a><h4 class="code-header">pub fn <a href="#method.new_unowned" class="fnname">new_unowned</a>(waker: ManuallyDrop<Waker>) -> Self</h4></section></summary><div class="docblock"><p>Create a new <a href="struct.WakerRef.html" title="WakerRef"><code>WakerRef</code></a> from a [<code>Waker</code>] that must not be dropped.</p> |
| <p>Note: this if for rare cases where the caller created a [<code>Waker</code>] in |
| an unsafe way (that will be valid only for a lifetime to be determined |
| by the caller), and the [<code>Waker</code>] doesn’t need to or must not be |
| destroyed.</p> |
| </div></details></div></details></div><h2 id="deref-methods-Waker" class="small-section-header"><span>Methods from Deref<Target = Waker></span><a href="#deref-methods-Waker" class="anchor"></a></h2><div id="deref-methods-Waker-1"><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.wake_by_ref" class="method has-srclink"><span class="since rightside" title="Stable since Rust version 1.36.0">1.36.0</span><h4 class="code-header">pub fn <a href="#method.wake_by_ref" class="fnname">wake_by_ref</a>(&self)</h4></section></summary><div class="docblock"><p>Wake up the task associated with this <code>Waker</code> without consuming the <code>Waker</code>.</p> |
| <p>This is similar to <a href="Self::wake"><code>wake()</code></a>, but may be slightly less efficient in |
| the case where an owned <code>Waker</code> is available. This method should be preferred to |
| calling <code>waker.clone().wake()</code>.</p> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.will_wake" class="method has-srclink"><span class="since rightside" title="Stable since Rust version 1.36.0">1.36.0</span><h4 class="code-header">pub fn <a href="#method.will_wake" class="fnname">will_wake</a>(&self, other: &Waker) -> bool</h4></section></summary><div class="docblock"><p>Returns <code>true</code> if this <code>Waker</code> and another <code>Waker</code> would awake the same task.</p> |
| <p>This function works on a best-effort basis, and may return false even |
| when the <code>Waker</code>s would awaken the same task. However, if this function |
| returns <code>true</code>, it is guaranteed that the <code>Waker</code>s will awaken the same task.</p> |
| <p>This function is primarily used for optimization purposes.</p> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.as_raw" class="method has-srclink"><h4 class="code-header">pub fn <a href="#method.as_raw" class="fnname">as_raw</a>(&self) -> &RawWaker</h4></section><span class="item-info"><div class="stab unstable"><span class="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>waker_getters</code>)</span></div></span></summary><div class="docblock"><p>Get a reference to the underlying [<code>RawWaker</code>].</p> |
| </div></details></div></div><h2 id="trait-implementations" class="small-section-header">Trait Implementations<a href="#trait-implementations" class="anchor"></a></h2><div id="trait-implementations-list"><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-Debug-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a class="srclink rightside" href="../src/futures_task/waker_ref.rs.html#13">source</a><a href="#impl-Debug-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<'a> Debug for <a class="struct" href="struct.WakerRef.html" title="struct futures_task::WakerRef">WakerRef</a><'a></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.fmt" class="method trait-impl has-srclink"><a class="srclink rightside" href="../src/futures_task/waker_ref.rs.html#13">source</a><a href="#method.fmt" class="anchor"></a><h4 class="code-header">fn <a class="fnname">fmt</a>(&self, f: &mut Formatter<'_>) -> Result</h4></section></summary><div class='docblock'>Formats the value using the given formatter. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-Deref-for-WakerRef%3C%27_%3E" class="impl has-srclink"><a class="srclink rightside" href="../src/futures_task/waker_ref.rs.html#41-48">source</a><a href="#impl-Deref-for-WakerRef%3C%27_%3E" class="anchor"></a><h3 class="code-header">impl Deref for <a class="struct" href="struct.WakerRef.html" title="struct futures_task::WakerRef">WakerRef</a><'_></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle" open><summary><section id="associatedtype.Target" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.Target" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">Target</a> = Waker</h4></section></summary><div class='docblock'>The resulting type after dereferencing.</div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.deref" class="method trait-impl has-srclink"><a class="srclink rightside" href="../src/futures_task/waker_ref.rs.html#45-47">source</a><a href="#method.deref" class="anchor"></a><h4 class="code-header">fn <a class="fnname">deref</a>(&self) -> &Waker</h4></section></summary><div class='docblock'>Dereferences the value.</div></details></div></details></div><h2 id="synthetic-implementations" class="small-section-header">Auto Trait Implementations<a href="#synthetic-implementations" class="anchor"></a></h2><div id="synthetic-implementations-list"><section id="impl-RefUnwindSafe-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a href="#impl-RefUnwindSafe-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<'a> RefUnwindSafe for <a class="struct" href="struct.WakerRef.html" title="struct futures_task::WakerRef">WakerRef</a><'a></h3></section><section id="impl-Send-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a href="#impl-Send-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<'a> Send for <a class="struct" href="struct.WakerRef.html" title="struct futures_task::WakerRef">WakerRef</a><'a></h3></section><section id="impl-Sync-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a href="#impl-Sync-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<'a> Sync for <a class="struct" href="struct.WakerRef.html" title="struct futures_task::WakerRef">WakerRef</a><'a></h3></section><section id="impl-Unpin-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a href="#impl-Unpin-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<'a> Unpin for <a class="struct" href="struct.WakerRef.html" title="struct futures_task::WakerRef">WakerRef</a><'a></h3></section><section id="impl-UnwindSafe-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a href="#impl-UnwindSafe-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<'a> UnwindSafe for <a class="struct" href="struct.WakerRef.html" title="struct futures_task::WakerRef">WakerRef</a><'a></h3></section></div><h2 id="blanket-implementations" class="small-section-header">Blanket Implementations<a href="#blanket-implementations" class="anchor"></a></h2><div id="blanket-implementations-list"><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-Any-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a href="#impl-Any-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<T> Any for T<span class="where fmt-newline">where<br> T: 'static + ?Sized,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.type_id" class="method trait-impl has-srclink"><a href="#method.type_id" class="anchor"></a><h4 class="code-header">fn <a class="fnname">type_id</a>(&self) -> TypeId</h4></section></summary><div class='docblock'>Gets the <code>TypeId</code> of <code>self</code>. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-Borrow%3CT%3E-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a href="#impl-Borrow%3CT%3E-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<T> Borrow<T> for T<span class="where fmt-newline">where<br> T: ?Sized,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.borrow" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/91522" title="Tracking issue for const_borrow">unstable</a></span><a href="#method.borrow" class="anchor"></a><h4 class="code-header">fn <a class="fnname">borrow</a>(&self) -> &T</h4></section></summary><div class='docblock'>Immutably borrows from an owned value. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-BorrowMut%3CT%3E-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a href="#impl-BorrowMut%3CT%3E-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<T> BorrowMut<T> for T<span class="where fmt-newline">where<br> T: ?Sized,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.borrow_mut" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/91522" title="Tracking issue for const_borrow">unstable</a></span><a href="#method.borrow_mut" class="anchor"></a><h4 class="code-header">fn <a class="fnname">borrow_mut</a>(&mut self) -> &mut T</h4></section></summary><div class='docblock'>Mutably borrows from an owned value. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-From%3CT%3E-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a href="#impl-From%3CT%3E-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<T> From<T> for T</h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.from" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/88674" title="Tracking issue for const_convert">unstable</a></span><a href="#method.from" class="anchor"></a><h4 class="code-header">fn <a class="fnname">from</a>(t: T) -> T</h4></section></summary><div class="docblock"><p>Returns the argument unchanged.</p> |
| </div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-Into%3CU%3E-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a href="#impl-Into%3CU%3E-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<T, U> Into<U> for T<span class="where fmt-newline">where<br> U: From<T>,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.into" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/88674" title="Tracking issue for const_convert">unstable</a></span><a href="#method.into" class="anchor"></a><h4 class="code-header">fn <a class="fnname">into</a>(self) -> U</h4></section></summary><div class="docblock"><p>Calls <code>U::from(self)</code>.</p> |
| <p>That is, this conversion is whatever the implementation of |
| <code>[From]<T> for U</code> chooses to do.</p> |
| </div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-TryFrom%3CU%3E-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a href="#impl-TryFrom%3CU%3E-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<T, U> TryFrom<U> for T<span class="where fmt-newline">where<br> U: Into<T>,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle" open><summary><section id="associatedtype.Error-1" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.Error-1" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">Error</a> = Infallible</h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.try_from" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/88674" title="Tracking issue for const_convert">unstable</a></span><a href="#method.try_from" class="anchor"></a><h4 class="code-header">fn <a class="fnname">try_from</a>(value: U) -> Result<T, <T as TryFrom<U>>::Error></h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-TryInto%3CU%3E-for-WakerRef%3C%27a%3E" class="impl has-srclink"><a href="#impl-TryInto%3CU%3E-for-WakerRef%3C%27a%3E" class="anchor"></a><h3 class="code-header">impl<T, U> TryInto<U> for T<span class="where fmt-newline">where<br> U: TryFrom<T>,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle" open><summary><section id="associatedtype.Error" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.Error" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">Error</a> = <U as TryFrom<T>>::Error</h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.try_into" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/88674" title="Tracking issue for const_convert">unstable</a></span><a href="#method.try_into" class="anchor"></a><h4 class="code-header">fn <a class="fnname">try_into</a>(self) -> Result<U, <U as TryFrom<T>>::Error></h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details></div></section></div></main><div id="rustdoc-vars" data-root-path="../" data-current-crate="futures_task" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
