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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="API documentation for the Rust `Backoff` struct in crate `crossbeam`."><meta name="keywords" content="rust, rustlang, rust-lang, Backoff"><title>crossbeam::utils::Backoff - Rust</title><link rel="stylesheet" type="text/css" href="../../normalize.css"><link rel="stylesheet" type="text/css" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" type="text/css" href="../../dark.css"><link rel="stylesheet" type="text/css" href="../../light.css" id="themeStyle"><script src="../../storage.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="shortcut icon" href="../../favicon.ico"><style type="text/css">#crate-search{background-image:url("../../down-arrow.svg");}</style></head><body class="rustdoc struct"><!--[if lte IE 8]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="sidebar-menu">&#9776;</div><a href='../../crossbeam/index.html'><div class='logo-container'><img src='../../rust-logo.png' alt='logo'></div></a><p class='location'>Struct Backoff</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#methods">Methods</a><div class="sidebar-links"><a href="#method.is_completed">is_completed</a><a href="#method.new">new</a><a href="#method.reset">reset</a><a href="#method.snooze">snooze</a><a href="#method.spin">spin</a></div><a class="sidebar-title" href="#implementations">Trait Implementations</a><div class="sidebar-links"><a href="#impl-Debug">Debug</a><a href="#impl-Default">Default</a></div><a class="sidebar-title" href="#synthetic-implementations">Auto Trait Implementations</a><div class="sidebar-links"><a href="#impl-RefUnwindSafe">!RefUnwindSafe</a><a href="#impl-Send">Send</a><a href="#impl-Sync">!Sync</a><a href="#impl-Unpin">Unpin</a><a href="#impl-UnwindSafe">UnwindSafe</a></div><a class="sidebar-title" href="#blanket-implementations">Blanket Implementations</a><div class="sidebar-links"><a href="#impl-Any">Any</a><a href="#impl-Borrow%3CT%3E">Borrow&lt;T&gt;</a><a href="#impl-BorrowMut%3CT%3E">BorrowMut&lt;T&gt;</a><a href="#impl-From%3CT%3E">From&lt;T&gt;</a><a href="#impl-Into%3CU%3E">Into&lt;U&gt;</a><a href="#impl-TryFrom%3CU%3E">TryFrom&lt;U&gt;</a><a href="#impl-TryInto%3CU%3E">TryInto&lt;U&gt;</a></div></div><p class='location'><a href='../index.html'>crossbeam</a>::<wbr><a href='index.html'>utils</a></p><script>window.sidebarCurrent = {name: 'Backoff', ty: 'struct', relpath: ''};</script><script defer src="sidebar-items.js"></script></div></nav><div class="theme-picker"><button id="theme-picker" aria-label="Pick another theme!"><img src="../../brush.svg" width="18" alt="Pick another theme!"></button><div id="theme-choices"></div></div><script src="../../theme.js"></script><nav class="sub"><form class="search-form js-only"><div class="search-container"><div><select id="crate-search"><option value="All crates">All crates</option></select><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press S to search, ? for more options…" type="search"></div><a id="settings-menu" href="../../settings.html"><img src="../../wheel.svg" width="18" alt="Change settings"></a></div></form></nav><section id="main" class="content"><h1 class='fqn'><span class='out-of-band'><span id='render-detail'><a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class='inner'>&#x2212;</span>]</a></span><a class='srclink' href='../../src/crossbeam_utils/backoff.rs.html#80-82' title='goto source code'>[src]</a></span><span class='in-band'>Struct <a href='../index.html'>crossbeam</a>::<wbr><a href='index.html'>utils</a>::<wbr><a class="struct" href=''>Backoff</a></span></h1><div class="docblock type-decl hidden-by-usual-hider"><pre class='rust struct'>pub struct Backoff { /*
<p>Backing off in spin loops reduces contention and improves overall performance.</p>
<p>This primitive can execute <em>YIELD</em> and <em>PAUSE</em> instructions, yield the current thread to the OS
scheduler, and tell when is a good time to block the thread using a different synchronization
mechanism. Each step of the back off procedure takes roughly twice as long as the previous
step.</p>
<h1 id="examples" class="section-header"><a href="#examples">Examples</a></h1>
<p>Backing off in a lock-free loop:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">crossbeam_utils</span>::<span class="ident">Backoff</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">atomic</span>::<span class="ident">AtomicUsize</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">atomic</span>::<span class="ident">Ordering</span>::<span class="ident">SeqCst</span>;
<span class="kw">fn</span> <span class="ident">fetch_mul</span>(<span class="ident">a</span>: <span class="kw-2">&amp;</span><span class="ident">AtomicUsize</span>, <span class="ident">b</span>: <span class="ident">usize</span>) <span class="op">-</span><span class="op">&gt;</span> <span class="ident">usize</span> {
<span class="kw">let</span> <span class="ident">backoff</span> <span class="op">=</span> <span class="ident">Backoff</span>::<span class="ident">new</span>();
<span class="kw">loop</span> {
<span class="kw">let</span> <span class="ident">val</span> <span class="op">=</span> <span class="ident">a</span>.<span class="ident">load</span>(<span class="ident">SeqCst</span>);
<span class="kw">if</span> <span class="ident">a</span>.<span class="ident">compare_and_swap</span>(<span class="ident">val</span>, <span class="ident">val</span>.<span class="ident">wrapping_mul</span>(<span class="ident">b</span>), <span class="ident">SeqCst</span>) <span class="op">=</span><span class="op">=</span> <span class="ident">val</span> {
<span class="kw">return</span> <span class="ident">val</span>;
}
<span class="ident">backoff</span>.<span class="ident">spin</span>();
}
}</pre></div>
<p>Waiting for an <a href="https://doc.rust-lang.org/std/sync/atomic/struct.AtomicBool.html"><code>AtomicBool</code></a> to become <code>true</code>:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">crossbeam_utils</span>::<span class="ident">Backoff</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">atomic</span>::<span class="ident">AtomicBool</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">atomic</span>::<span class="ident">Ordering</span>::<span class="ident">SeqCst</span>;
<span class="kw">fn</span> <span class="ident">spin_wait</span>(<span class="ident">ready</span>: <span class="kw-2">&amp;</span><span class="ident">AtomicBool</span>) {
<span class="kw">let</span> <span class="ident">backoff</span> <span class="op">=</span> <span class="ident">Backoff</span>::<span class="ident">new</span>();
<span class="kw">while</span> <span class="op">!</span><span class="ident">ready</span>.<span class="ident">load</span>(<span class="ident">SeqCst</span>) {
<span class="ident">backoff</span>.<span class="ident">snooze</span>();
}
}</pre></div>
<p>Waiting for an <a href="https://doc.rust-lang.org/std/sync/atomic/struct.AtomicBool.html"><code>AtomicBool</code></a> to become <code>true</code> and parking the thread after a long wait.
Note that whoever sets the atomic variable to <code>true</code> must notify the parked thread by calling
<a href="https://doc.rust-lang.org/std/thread/struct.Thread.html#method.unpark"><code>unpark()</code></a>:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">crossbeam_utils</span>::<span class="ident">Backoff</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">atomic</span>::<span class="ident">AtomicBool</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">atomic</span>::<span class="ident">Ordering</span>::<span class="ident">SeqCst</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">thread</span>;
<span class="kw">fn</span> <span class="ident">blocking_wait</span>(<span class="ident">ready</span>: <span class="kw-2">&amp;</span><span class="ident">AtomicBool</span>) {
<span class="kw">let</span> <span class="ident">backoff</span> <span class="op">=</span> <span class="ident">Backoff</span>::<span class="ident">new</span>();
<span class="kw">while</span> <span class="op">!</span><span class="ident">ready</span>.<span class="ident">load</span>(<span class="ident">SeqCst</span>) {
<span class="kw">if</span> <span class="ident">backoff</span>.<span class="ident">is_completed</span>() {
<span class="ident">thread</span>::<span class="ident">park</span>();
} <span class="kw">else</span> {
<span class="ident">backoff</span>.<span class="ident">snooze</span>();
}
}
}</pre></div>
</div><h2 id='methods' class='small-section-header'>Methods<a href='#methods' class='anchor'></a></h2><h3 id='impl' class='impl'><code class='in-band'>impl <a class="struct" href="../../crossbeam/utils/struct.Backoff.html" title="struct crossbeam::utils::Backoff">Backoff</a></code><a href='#impl' class='anchor'></a><a class='srclink' href='../../src/crossbeam_utils/backoff.rs.html#84-279' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.new' class="method"><code id='new.v'>pub fn <a href='#method.new' class='fnname'>new</a>() -&gt; <a class="struct" href="../../crossbeam/utils/struct.Backoff.html" title="struct crossbeam::utils::Backoff">Backoff</a></code><a class='srclink' href='../../src/crossbeam_utils/backoff.rs.html#95-99' title='goto source code'>[src]</a></h4><div class='docblock'><p>Creates a new <code>Backoff</code>.</p>
<h1 id="examples-1" class="section-header"><a href="#examples-1">Examples</a></h1>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">crossbeam_utils</span>::<span class="ident">Backoff</span>;
<span class="kw">let</span> <span class="ident">backoff</span> <span class="op">=</span> <span class="ident">Backoff</span>::<span class="ident">new</span>();</pre></div>
</div><h4 id='method.reset' class="method"><code id='reset.v'>pub fn <a href='#method.reset' class='fnname'>reset</a>(&amp;self)</code><a class='srclink' href='../../src/crossbeam_utils/backoff.rs.html#112-114' title='goto source code'>[src]</a></h4><div class='docblock'><p>Resets the <code>Backoff</code>.</p>
<h1 id="examples-2" class="section-header"><a href="#examples-2">Examples</a></h1>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">crossbeam_utils</span>::<span class="ident">Backoff</span>;
<span class="kw">let</span> <span class="ident">backoff</span> <span class="op">=</span> <span class="ident">Backoff</span>::<span class="ident">new</span>();
<span class="ident">backoff</span>.<span class="ident">reset</span>();</pre></div>
</div><h4 id='method.spin' class="method"><code id='spin.v'>pub fn <a href='#method.spin' class='fnname'>spin</a>(&amp;self)</code><a class='srclink' href='../../src/crossbeam_utils/backoff.rs.html#148-156' title='goto source code'>[src]</a></h4><div class='docblock'><p>Backs off in a lock-free loop.</p>
<p>This method should be used when we need to retry an operation because another thread made
progress.</p>
<p>The processor may yield using the <em>YIELD</em> or <em>PAUSE</em> instruction.</p>
<h1 id="examples-3" class="section-header"><a href="#examples-3">Examples</a></h1>
<p>Backing off in a lock-free loop:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">crossbeam_utils</span>::<span class="ident">Backoff</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">atomic</span>::<span class="ident">AtomicUsize</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">atomic</span>::<span class="ident">Ordering</span>::<span class="ident">SeqCst</span>;
<span class="kw">fn</span> <span class="ident">fetch_mul</span>(<span class="ident">a</span>: <span class="kw-2">&amp;</span><span class="ident">AtomicUsize</span>, <span class="ident">b</span>: <span class="ident">usize</span>) <span class="op">-</span><span class="op">&gt;</span> <span class="ident">usize</span> {
<span class="kw">let</span> <span class="ident">backoff</span> <span class="op">=</span> <span class="ident">Backoff</span>::<span class="ident">new</span>();
<span class="kw">loop</span> {
<span class="kw">let</span> <span class="ident">val</span> <span class="op">=</span> <span class="ident">a</span>.<span class="ident">load</span>(<span class="ident">SeqCst</span>);
<span class="kw">if</span> <span class="ident">a</span>.<span class="ident">compare_and_swap</span>(<span class="ident">val</span>, <span class="ident">val</span>.<span class="ident">wrapping_mul</span>(<span class="ident">b</span>), <span class="ident">SeqCst</span>) <span class="op">=</span><span class="op">=</span> <span class="ident">val</span> {
<span class="kw">return</span> <span class="ident">val</span>;
}
<span class="ident">backoff</span>.<span class="ident">spin</span>();
}
}
<span class="kw">let</span> <span class="ident">a</span> <span class="op">=</span> <span class="ident">AtomicUsize</span>::<span class="ident">new</span>(<span class="number">7</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">fetch_mul</span>(<span class="kw-2">&amp;</span><span class="ident">a</span>, <span class="number">8</span>), <span class="number">7</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">a</span>.<span class="ident">load</span>(<span class="ident">SeqCst</span>), <span class="number">56</span>);</pre></div>
</div><h4 id='method.snooze' class="method"><code id='snooze.v'>pub fn <a href='#method.snooze' class='fnname'>snooze</a>(&amp;self)</code><a class='srclink' href='../../src/crossbeam_utils/backoff.rs.html#207-225' title='goto source code'>[src]</a></h4><div class='docblock'><p>Backs off in a blocking loop.</p>
<p>This method should be used when we need to wait for another thread to make progress.</p>
<p>The processor may yield using the <em>YIELD</em> or <em>PAUSE</em> instruction and the current thread
may yield by giving up a timeslice to the OS scheduler.</p>
<p>In <code>#[no_std]</code> environments, this method is equivalent to <a href="struct.Backoff.html#method.spin"><code>spin</code></a>.</p>
<p>If possible, use <a href="struct.Backoff.html#method.is_completed"><code>is_completed</code></a> to check when it is advised to stop using backoff and
block the current thread using a different synchronization mechanism instead.</p>
<h1 id="examples-4" class="section-header"><a href="#examples-4">Examples</a></h1>
<p>Waiting for an <a href="https://doc.rust-lang.org/std/sync/atomic/struct.AtomicBool.html"><code>AtomicBool</code></a> to become <code>true</code>:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">crossbeam_utils</span>::<span class="ident">Backoff</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">Arc</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">atomic</span>::<span class="ident">AtomicBool</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">atomic</span>::<span class="ident">Ordering</span>::<span class="ident">SeqCst</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">thread</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">time</span>::<span class="ident">Duration</span>;
<span class="kw">fn</span> <span class="ident">spin_wait</span>(<span class="ident">ready</span>: <span class="kw-2">&amp;</span><span class="ident">AtomicBool</span>) {
<span class="kw">let</span> <span class="ident">backoff</span> <span class="op">=</span> <span class="ident">Backoff</span>::<span class="ident">new</span>();
<span class="kw">while</span> <span class="op">!</span><span class="ident">ready</span>.<span class="ident">load</span>(<span class="ident">SeqCst</span>) {
<span class="ident">backoff</span>.<span class="ident">snooze</span>();
}
}
<span class="kw">let</span> <span class="ident">ready</span> <span class="op">=</span> <span class="ident">Arc</span>::<span class="ident">new</span>(<span class="ident">AtomicBool</span>::<span class="ident">new</span>(<span class="bool-val">false</span>));
<span class="kw">let</span> <span class="ident">ready2</span> <span class="op">=</span> <span class="ident">ready</span>.<span class="ident">clone</span>();
<span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span> <span class="op">|</span><span class="op">|</span> {
<span class="ident">thread</span>::<span class="ident">sleep</span>(<span class="ident">Duration</span>::<span class="ident">from_millis</span>(<span class="number">100</span>));
<span class="ident">ready2</span>.<span class="ident">store</span>(<span class="bool-val">true</span>, <span class="ident">SeqCst</span>);
});
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">ready</span>.<span class="ident">load</span>(<span class="ident">SeqCst</span>), <span class="bool-val">false</span>);
<span class="ident">spin_wait</span>(<span class="kw-2">&amp;</span><span class="ident">ready</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">ready</span>.<span class="ident">load</span>(<span class="ident">SeqCst</span>), <span class="bool-val">true</span>);</pre></div>
</div><h4 id='method.is_completed' class="method"><code id='is_completed.v'>pub fn <a href='#method.is_completed' class='fnname'>is_completed</a>(&amp;self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a></code><a class='srclink' href='../../src/crossbeam_utils/backoff.rs.html#269-271' title='goto source code'>[src]</a></h4><div class='docblock'><p>Returns <code>true</code> if exponential backoff has completed and blocking the thread is advised.</p>
<h1 id="examples-5" class="section-header"><a href="#examples-5">Examples</a></h1>
<p>Waiting for an <a href="https://doc.rust-lang.org/std/sync/atomic/struct.AtomicBool.html"><code>AtomicBool</code></a> to become <code>true</code> and parking the thread after a long wait:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">crossbeam_utils</span>::<span class="ident">Backoff</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">Arc</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">atomic</span>::<span class="ident">AtomicBool</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">atomic</span>::<span class="ident">Ordering</span>::<span class="ident">SeqCst</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">thread</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">time</span>::<span class="ident">Duration</span>;
<span class="kw">fn</span> <span class="ident">blocking_wait</span>(<span class="ident">ready</span>: <span class="kw-2">&amp;</span><span class="ident">AtomicBool</span>) {
<span class="kw">let</span> <span class="ident">backoff</span> <span class="op">=</span> <span class="ident">Backoff</span>::<span class="ident">new</span>();
<span class="kw">while</span> <span class="op">!</span><span class="ident">ready</span>.<span class="ident">load</span>(<span class="ident">SeqCst</span>) {
<span class="kw">if</span> <span class="ident">backoff</span>.<span class="ident">is_completed</span>() {
<span class="ident">thread</span>::<span class="ident">park</span>();
} <span class="kw">else</span> {
<span class="ident">backoff</span>.<span class="ident">snooze</span>();
}
}
}
<span class="kw">let</span> <span class="ident">ready</span> <span class="op">=</span> <span class="ident">Arc</span>::<span class="ident">new</span>(<span class="ident">AtomicBool</span>::<span class="ident">new</span>(<span class="bool-val">false</span>));
<span class="kw">let</span> <span class="ident">ready2</span> <span class="op">=</span> <span class="ident">ready</span>.<span class="ident">clone</span>();
<span class="kw">let</span> <span class="ident">waiter</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">current</span>();
<span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span> <span class="op">|</span><span class="op">|</span> {
<span class="ident">thread</span>::<span class="ident">sleep</span>(<span class="ident">Duration</span>::<span class="ident">from_millis</span>(<span class="number">100</span>));
<span class="ident">ready2</span>.<span class="ident">store</span>(<span class="bool-val">true</span>, <span class="ident">SeqCst</span>);
<span class="ident">waiter</span>.<span class="ident">unpark</span>();
});
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">ready</span>.<span class="ident">load</span>(<span class="ident">SeqCst</span>), <span class="bool-val">false</span>);
<span class="ident">blocking_wait</span>(<span class="kw-2">&amp;</span><span class="ident">ready</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">ready</span>.<span class="ident">load</span>(<span class="ident">SeqCst</span>), <span class="bool-val">true</span>);</pre></div>
</div></div><h2 id='implementations' class='small-section-header'>Trait Implementations<a href='#implementations' class='anchor'></a></h2><div id='implementations-list'><h3 id='impl-Debug' class='impl'><code class='in-band'>impl <a class="trait" href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> for <a class="struct" href="../../crossbeam/utils/struct.Backoff.html" title="struct crossbeam::utils::Backoff">Backoff</a></code><a href='#impl-Debug' class='anchor'></a><a class='srclink' href='../../src/crossbeam_utils/backoff.rs.html#281-288' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.fmt' class="method hidden"><code id='fmt.v'>fn <a href='https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt' class='fnname'>fmt</a>(&amp;self, f: &amp;mut <a class="struct" href="https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a>) -&gt; <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>, <a class="struct" href="https://doc.rust-lang.org/nightly/core/fmt/struct.Error.html" title="struct core::fmt::Error">Error</a>&gt;</code><a class='srclink' href='../../src/crossbeam_utils/backoff.rs.html#282-287' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Formats the value using the given formatter. <a href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></p>
</div></div><h3 id='impl-Default' class='impl'><code class='in-band'>impl <a class="trait" href="https://doc.rust-lang.org/nightly/core/default/trait.Default.html" title="trait core::default::Default">Default</a> for <a class="struct" href="../../crossbeam/utils/struct.Backoff.html" title="struct crossbeam::utils::Backoff">Backoff</a></code><a href='#impl-Default' class='anchor'></a><a class='srclink' href='../../src/crossbeam_utils/backoff.rs.html#290-294' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.default' class="method hidden"><code id='default.v'>fn <a href='https://doc.rust-lang.org/nightly/core/default/trait.Default.html#tymethod.default' class='fnname'>default</a>() -&gt; <a class="struct" href="../../crossbeam/utils/struct.Backoff.html" title="struct crossbeam::utils::Backoff">Backoff</a></code><a class='srclink' href='../../src/crossbeam_utils/backoff.rs.html#291-293' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Returns the &quot;default value&quot; for a type. <a href="https://doc.rust-lang.org/nightly/core/default/trait.Default.html#tymethod.default">Read more</a></p>
</div></div></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'><h3 id='impl-Send' class='impl'><code class='in-band'>impl <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> for <a class="struct" href="../../crossbeam/utils/struct.Backoff.html" title="struct crossbeam::utils::Backoff">Backoff</a></code><a href='#impl-Send' class='anchor'></a></h3><div class='impl-items'></div><h3 id='impl-Unpin' class='impl'><code class='in-band'>impl <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Unpin.html" title="trait core::marker::Unpin">Unpin</a> for <a class="struct" href="../../crossbeam/utils/struct.Backoff.html" title="struct crossbeam::utils::Backoff">Backoff</a></code><a href='#impl-Unpin' class='anchor'></a></h3><div class='impl-items'></div><h3 id='impl-Sync' class='impl'><code class='in-band'>impl !<a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> for <a class="struct" href="../../crossbeam/utils/struct.Backoff.html" title="struct crossbeam::utils::Backoff">Backoff</a></code><a href='#impl-Sync' class='anchor'></a></h3><div class='impl-items'></div><h3 id='impl-UnwindSafe' class='impl'><code class='in-band'>impl <a class="trait" href="https://doc.rust-lang.org/nightly/std/panic/trait.UnwindSafe.html" title="trait std::panic::UnwindSafe">UnwindSafe</a> for <a class="struct" href="../../crossbeam/utils/struct.Backoff.html" title="struct crossbeam::utils::Backoff">Backoff</a></code><a href='#impl-UnwindSafe' class='anchor'></a></h3><div class='impl-items'></div><h3 id='impl-RefUnwindSafe' class='impl'><code class='in-band'>impl !<a class="trait" href="https://doc.rust-lang.org/nightly/std/panic/trait.RefUnwindSafe.html" title="trait std::panic::RefUnwindSafe">RefUnwindSafe</a> for <a class="struct" href="../../crossbeam/utils/struct.Backoff.html" title="struct crossbeam::utils::Backoff">Backoff</a></code><a href='#impl-RefUnwindSafe' class='anchor'></a></h3><div class='impl-items'></div></div><h2 id='blanket-implementations' class='small-section-header'>Blanket Implementations<a href='#blanket-implementations' class='anchor'></a></h2><div id='blanket-implementations-list'><h3 id='impl-Into%3CU%3E' class='impl'><code class='in-band'>impl&lt;T, U&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/convert/trait.Into.html" title="trait core::convert::Into">Into</a>&lt;U&gt; for T <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;U: <a class="trait" href="https://doc.rust-lang.org/nightly/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;T&gt;,&nbsp;</span></code><a href='#impl-Into%3CU%3E' class='anchor'></a><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/convert.rs.html#544-549' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.into' class="method hidden"><code id='into.v'>fn <a href='https://doc.rust-lang.org/nightly/core/convert/trait.Into.html#tymethod.into' class='fnname'>into</a>(self) -&gt; U</code><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/convert.rs.html#546-548' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Performs the conversion.</p>
</div></div><h3 id='impl-From%3CT%3E' class='impl'><code class='in-band'>impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;T&gt; for T</code><a href='#impl-From%3CT%3E' class='anchor'></a><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/convert.rs.html#553-555' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.from' class="method hidden"><code id='from.v'>fn <a href='https://doc.rust-lang.org/nightly/core/convert/trait.From.html#tymethod.from' class='fnname'>from</a>(t: T) -&gt; T</code><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/convert.rs.html#554' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Performs the conversion.</p>
</div></div><h3 id='impl-TryFrom%3CU%3E' class='impl'><code class='in-band'>impl&lt;T, U&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;U&gt; for T <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;U: <a class="trait" href="https://doc.rust-lang.org/nightly/core/convert/trait.Into.html" title="trait core::convert::Into">Into</a>&lt;T&gt;,&nbsp;</span></code><a href='#impl-TryFrom%3CU%3E' class='anchor'></a><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/convert.rs.html#572-578' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='associatedtype.Error' class="type"><code id='Error.t'>type <a href='https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html#associatedtype.Error' class="type">Error</a> = <a class="enum" href="https://doc.rust-lang.org/nightly/core/convert/enum.Infallible.html" title="enum core::convert::Infallible">Infallible</a></code></h4><div class='docblock'><p>The type returned in the event of a conversion error.</p>
</div><h4 id='method.try_from' class="method hidden"><code id='try_from.v'>fn <a href='https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html#tymethod.try_from' class='fnname'>try_from</a>(value: U) -&gt; <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;T, &lt;T as <a class="trait" href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;U&gt;&gt;::<a class="type" href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a>&gt;</code><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/convert.rs.html#575-577' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Performs the conversion.</p>
</div></div><h3 id='impl-TryInto%3CU%3E' class='impl'><code class='in-band'>impl&lt;T, U&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/convert/trait.TryInto.html" title="trait core::convert::TryInto">TryInto</a>&lt;U&gt; for T <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;U: <a class="trait" href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;T&gt;,&nbsp;</span></code><a href='#impl-TryInto%3CU%3E' class='anchor'></a><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/convert.rs.html#560-567' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='associatedtype.Error-1' class="type"><code id='Error.t-1'>type <a href='https://doc.rust-lang.org/nightly/core/convert/trait.TryInto.html#associatedtype.Error' class="type">Error</a> = &lt;U as <a class="trait" href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;T&gt;&gt;::<a class="type" href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a></code></h4><div class='docblock'><p>The type returned in the event of a conversion error.</p>
</div><h4 id='method.try_into' class="method hidden"><code id='try_into.v'>fn <a href='https://doc.rust-lang.org/nightly/core/convert/trait.TryInto.html#tymethod.try_into' class='fnname'>try_into</a>(self) -&gt; <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;U, &lt;U as <a class="trait" href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;T&gt;&gt;::<a class="type" href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a>&gt;</code><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/convert.rs.html#564-566' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Performs the conversion.</p>
</div></div><h3 id='impl-BorrowMut%3CT%3E' class='impl'><code class='in-band'>impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/borrow/trait.BorrowMut.html" title="trait core::borrow::BorrowMut">BorrowMut</a>&lt;T&gt; for T <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;T: ?<a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,&nbsp;</span></code><a href='#impl-BorrowMut%3CT%3E' class='anchor'></a><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/borrow.rs.html#218-220' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.borrow_mut' class="method hidden"><div class="important-traits"><div class='tooltip'><span class='tooltiptext'>Important traits for <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;'_ mut </a>W</span></div><div class="content hidden"><h3 class="important">Important traits for <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;'_ mut </a>W</h3><code class="content"><span class="where fmt-newline">impl&lt;'_, W&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;'_ mut </a>W <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;W: <a class="trait" href="https://doc.rust-lang.org/nightly/std/io/trait.Write.html" title="trait std::io::Write">Write</a> + ?<a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,&nbsp;</span></span><span class="where fmt-newline">impl&lt;'_, R&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/std/io/trait.Read.html" title="trait std::io::Read">Read</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;'_ mut </a>R <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;R: <a class="trait" href="https://doc.rust-lang.org/nightly/std/io/trait.Read.html" title="trait std::io::Read">Read</a> + ?<a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,&nbsp;</span></span><span class="where fmt-newline">impl&lt;'_, I&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/iter/traits/iterator/trait.Iterator.html" title="trait core::iter::traits::iterator::Iterator">Iterator</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;'_ mut </a>I <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;I: <a class="trait" href="https://doc.rust-lang.org/nightly/core/iter/traits/iterator/trait.Iterator.html" title="trait core::iter::traits::iterator::Iterator">Iterator</a> + ?<a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,&nbsp;</span></span><span class="where fmt-newline"> type <a href='https://doc.rust-lang.org/nightly/core/iter/traits/iterator/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = &lt;I as <a class="trait" href="https://doc.rust-lang.org/nightly/core/iter/traits/iterator/trait.Iterator.html" title="trait core::iter::traits::iterator::Iterator">Iterator</a>&gt;::<a class="type" href="https://doc.rust-lang.org/nightly/core/iter/traits/iterator/trait.Iterator.html#associatedtype.Item" title="type core::iter::traits::iterator::Iterator::Item">Item</a>;</span><span class="where fmt-newline">impl&lt;'_, F&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/future/future/trait.Future.html" title="trait core::future::future::Future">Future</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;'_ mut </a>F <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;F: <a class="trait" href="https://d
</div></div><h3 id='impl-Borrow%3CT%3E' class='impl'><code class='in-band'>impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/borrow/trait.Borrow.html" title="trait core::borrow::Borrow">Borrow</a>&lt;T&gt; for T <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;T: ?<a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,&nbsp;</span></code><a href='#impl-Borrow%3CT%3E' class='anchor'></a><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/borrow.rs.html#213-215' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.borrow' class="method hidden"><div class="important-traits"><div class='tooltip'><span class='tooltiptext'>Important traits for <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;'_ mut </a>W</span></div><div class="content hidden"><h3 class="important">Important traits for <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;'_ mut </a>W</h3><code class="content"><span class="where fmt-newline">impl&lt;'_, W&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;'_ mut </a>W <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;W: <a class="trait" href="https://doc.rust-lang.org/nightly/std/io/trait.Write.html" title="trait std::io::Write">Write</a> + ?<a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,&nbsp;</span></span><span class="where fmt-newline">impl&lt;'_, R&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/std/io/trait.Read.html" title="trait std::io::Read">Read</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;'_ mut </a>R <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;R: <a class="trait" href="https://doc.rust-lang.org/nightly/std/io/trait.Read.html" title="trait std::io::Read">Read</a> + ?<a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,&nbsp;</span></span><span class="where fmt-newline">impl&lt;'_, I&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/iter/traits/iterator/trait.Iterator.html" title="trait core::iter::traits::iterator::Iterator">Iterator</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;'_ mut </a>I <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;I: <a class="trait" href="https://doc.rust-lang.org/nightly/core/iter/traits/iterator/trait.Iterator.html" title="trait core::iter::traits::iterator::Iterator">Iterator</a> + ?<a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,&nbsp;</span></span><span class="where fmt-newline"> type <a href='https://doc.rust-lang.org/nightly/core/iter/traits/iterator/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = &lt;I as <a class="trait" href="https://doc.rust-lang.org/nightly/core/iter/traits/iterator/trait.Iterator.html" title="trait core::iter::traits::iterator::Iterator">Iterator</a>&gt;::<a class="type" href="https://doc.rust-lang.org/nightly/core/iter/traits/iterator/trait.Iterator.html#associatedtype.Item" title="type core::iter::traits::iterator::Iterator::Item">Item</a>;</span><span class="where fmt-newline">impl&lt;'_, F&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/future/future/trait.Future.html" title="trait core::future::future::Future">Future</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&amp;'_ mut </a>F <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;F: <a class="trait" href="https://doc.rust-lang.org/ni
</div></div><h3 id='impl-Any' class='impl'><code class='in-band'>impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/any/trait.Any.html" title="trait core::any::Any">Any</a> for T <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;T: 'static + ?<a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,&nbsp;</span></code><a href='#impl-Any' class='anchor'></a><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/any.rs.html#100-102' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.type_id' class="method hidden"><code id='type_id.v'>fn <a href='https://doc.rust-lang.org/nightly/core/any/trait.Any.html#tymethod.type_id' class='fnname'>type_id</a>(&amp;self) -&gt; <a class="struct" href="https://doc.rust-lang.org/nightly/core/any/struct.TypeId.html" title="struct core::any::TypeId">TypeId</a></code><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/any.rs.html#101' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Gets the <code>TypeId</code> of <code>self</code>. <a href="https://doc.rust-lang.org/nightly/core/any/trait.Any.html#tymethod.type_id">Read more</a></p>
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