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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="An asynchronous `Mutex`-like type."><title>Mutex in tokio::sync - Rust</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-6b053e98.ttf.woff2,FiraSans-Italic-81dc35de.woff2,FiraSans-Regular-0fe48ade.woff2,FiraSans-MediumItalic-ccf7e434.woff2,FiraSans-Medium-e1aa3f0a.woff2,SourceCodePro-Regular-8badfe75.ttf.woff2,SourceCodePro-Semibold-aa29a496.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2"href="../../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../../static.files/normalize-9960930a.css"><link rel="stylesheet" href="../../static.files/rustdoc-ca0dd0c4.css"><meta name="rustdoc-vars" data-root-path="../../" data-static-root-path="../../static.files/" data-current-crate="tokio" data-themes="" data-resource-suffix="" data-rustdoc-version="1.93.1 (01f6ddf75 2026-02-11) (Arch Linux rust 1:1.93.1-1)" data-channel="1.93.1" data-search-js="search-9e2438ea.js" data-stringdex-js="stringdex-a3946164.js" data-settings-js="settings-c38705f0.js" ><script src="../../static.files/storage-e2aeef58.js"></script><script defer src="sidebar-items.js"></script><script defer src="../../static.files/main-a410ff4d.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-263c88ec.css"></noscript><link rel="alternate icon" type="image/png" href="../../static.files/favicon-32x32-eab170b8.png"><link rel="icon" type="image/svg+xml" href="../../static.files/favicon-044be391.svg"></head><body class="rustdoc struct"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><rustdoc-topbar><h2><a href="#">Mutex</a></h2></rustdoc-topbar><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../tokio/index.html">tokio</a><span class="version">1.49.0</span></h2></div><div class="sidebar-elems"><section id="rustdoc-toc"><h2 class="location"><a href="#">Mutex</a></h2><h3><a href="#">Sections</a></h3><ul class="block top-toc"><li><a href="#which-kind-of-mutex-should-you-use" title="Which kind of mutex should you use?">Which kind of mutex should you use?</a></li><li><a href="#examples" title="Examples:">Examples:</a></li></ul><h3><a href="#implementations">Methods</a></h3><ul class="block method"><li><a href="#method.blocking_lock" title="blocking_lock">blocking_lock</a></li><li><a href="#method.blocking_lock_owned" title="blocking_lock_owned">blocking_lock_owned</a></li><li><a href="#method.const_new" title="const_new">const_new</a></li><li><a href="#method.get_mut" title="get_mut">get_mut</a></li><li><a href="#method.into_inner" title="into_inner">into_inner</a></li><li><a href="#method.lock" title="lock">lock</a></li><li><a href="#method.lock_owned" title="lock_owned">lock_owned</a></li><li><a href="#method.new" title="new">new</a></li><li><a href="#method.try_lock" title="try_lock">try_lock</a></li><li><a href="#method.try_lock_owned" title="try_lock_owned">try_lock_owned</a></li></ul><h3><a href="#trait-implementations">Trait Implementations</a></h3><ul class="block trait-implementation"><li><a href="#impl-Debug-for-Mutex%3CT%3E" title="Debug">Debug</a></li><li><a href="#impl-Default-for-Mutex%3CT%3E" title="Default">Default</a></li><li><a href="#impl-From%3CT%3E-for-Mutex%3CT%3E" title="From<T>">From<T></a></li><li><a href="#impl-Send-for-Mutex%3CT%3E" title="Send">Send</a></li><li><a href="#impl-Sync-for-Mutex%3CT%3E" title="Sync">Sync</a></li></ul><h3><a href="#synthetic-implementations">Auto Trait Implementations</a></h3><ul class="block synthetic-implementation"><li><a href="#impl-Freeze-for-Mutex%3CT%3E" title="!Freeze">!Freeze</a></li><li><a href="#impl-RefUnwindSafe-for-Mutex%3CT%3E" title="!RefUnwindSafe">!RefUnwindSafe</a></li><li><a href="#impl-UnwindSafe-for-Mutex%3CT%3E" title="!UnwindSafe">!UnwindSafe</a></li><li><a href="#impl-Unpin-for-Mutex%3CT%3E" title="Unpin">Unpin</a></li></ul><h3><a href="#blanket-implementations">Blanket Implementations</a></h3><ul class="block blanket-implementation"><li><a href="#impl-Any-for-T" title="Any">Any</a></li><li><a href="#impl-Borrow%3CT%3E-for-T" title="Borrow<T>">Borrow<T></a></li><li><a href="#impl-BorrowMut%3CT%3E-for-T" title="BorrowMut<T>">BorrowMut<T></a></li><li><a href="#impl-From%3C!%3E-for-T" title="From<!>">From<!></a></li><li><a href="#impl-From%3CT%3E-for-T" title="From<T>">From<T></a></li><li><a href="#impl-Into%3CU%3E-for-T" title="Into<U>">Into<U></a></li><li><a href="#impl-TryFrom%3CU%3E-for-T" title="TryFrom<U>">TryFrom<U></a></li><li><a href="#impl-TryInto%3CU%3E-for-T" title="TryInto<U>">TryInto<U></a></li></ul></section><div id="rustdoc-modnav"><h2><a href="index.html">In tokio::<wbr>sync</a></h2></div></div></nav><div class="sidebar-resizer" title="Drag to resize sidebar"></div><main><div class="width-limiter"><section id="main-content" class="content"><div class="main-heading"><div class="rustdoc-breadcrumbs"><a href="../index.html">tokio</a>::<wbr><a href="index.html">sync</a></div><h1>Struct <span class="struct">Mutex</span> <button id="copy-path" title="Copy item path to clipboard">Copy item path</button></h1><rustdoc-toolbar></rustdoc-toolbar><span class="sub-heading"><a class="src" href="../../src/tokio/sync/mutex.rs.html#133-138">Source</a> </span></div><pre class="rust item-decl"><code>pub struct Mutex<T: ?<a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> { <span class="comment">/* private fields */</span> }</code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>An asynchronous <code>Mutex</code>-like type.</p>
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<p>This type acts similarly to <a href="https://doc.rust-lang.org/1.93.1/std/sync/poison/mutex/struct.Mutex.html" title="struct std::sync::poison::mutex::Mutex"><code>std::sync::Mutex</code></a>, with two major
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differences: <a href="struct.Mutex.html#method.lock" title="method tokio::sync::Mutex::lock"><code>lock</code></a> is an async method so does not block, and the lock
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guard is designed to be held across <code>.await</code> points.</p>
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<p>Tokio’s Mutex operates on a guaranteed FIFO basis.
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This means that the order in which tasks call the <a href="struct.Mutex.html#method.lock" title="method tokio::sync::Mutex::lock"><code>lock</code></a> method is
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the exact order in which they will acquire the lock.</p>
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<h2 id="which-kind-of-mutex-should-you-use"><a class="doc-anchor" href="#which-kind-of-mutex-should-you-use">§</a>Which kind of mutex should you use?</h2>
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<p>Contrary to popular belief, it is ok and often preferred to use the ordinary
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<a href="https://doc.rust-lang.org/1.93.1/std/sync/poison/mutex/struct.Mutex.html" title="struct std::sync::poison::mutex::Mutex"><code>Mutex</code></a> from the standard library in asynchronous code.</p>
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<p>The feature that the async mutex offers over the blocking mutex is the
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ability to keep it locked across an <code>.await</code> point. This makes the async
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mutex more expensive than the blocking mutex, so the blocking mutex should
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be preferred in the cases where it can be used. The primary use case for the
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async mutex is to provide shared mutable access to IO resources such as a
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database connection. If the value behind the mutex is just data, it’s
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usually appropriate to use a blocking mutex such as the one in the standard
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library or <a href="https://docs.rs/parking_lot"><code>parking_lot</code></a>.</p>
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<p>Note that, although the compiler will not prevent the std <code>Mutex</code> from holding
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its guard across <code>.await</code> points in situations where the task is not movable
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between threads, this virtually never leads to correct concurrent code in
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practice as it can easily lead to deadlocks.</p>
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<p>A common pattern is to wrap the <code>Arc<Mutex<...>></code> in a struct that provides
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non-async methods for performing operations on the data within, and only
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lock the mutex inside these methods. The <a href="https://github.com/tokio-rs/mini-redis/blob/master/src/db.rs">mini-redis</a> example provides an
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illustration of this pattern.</p>
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<p>Additionally, when you <em>do</em> want shared access to an IO resource, it is
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often better to spawn a task to manage the IO resource, and to use message
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passing to communicate with that task.</p>
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<h2 id="examples"><a class="doc-anchor" href="#examples">§</a>Examples:</h2>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::Mutex;
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<span class="kw">use </span>std::sync::Arc;
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<span class="kw">let </span>data1 = Arc::new(Mutex::new(<span class="number">0</span>));
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<span class="kw">let </span>data2 = Arc::clone(<span class="kw-2">&</span>data1);
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tokio::spawn(<span class="kw">async move </span>{
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<span class="kw">let </span><span class="kw-2">mut </span>lock = data2.lock().<span class="kw">await</span>;
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<span class="kw-2">*</span>lock += <span class="number">1</span>;
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});
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<span class="kw">let </span><span class="kw-2">mut </span>lock = data1.lock().<span class="kw">await</span>;
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<span class="kw-2">*</span>lock += <span class="number">1</span>;</code></pre></div>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::Mutex;
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<span class="kw">use </span>std::sync::Arc;
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<span class="kw">let </span>count = Arc::new(Mutex::new(<span class="number">0</span>));
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<span class="kw">for </span>i <span class="kw">in </span><span class="number">0</span>..<span class="number">5 </span>{
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<span class="kw">let </span>my_count = Arc::clone(<span class="kw-2">&</span>count);
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tokio::spawn(<span class="kw">async move </span>{
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<span class="kw">for </span>j <span class="kw">in </span><span class="number">0</span>..<span class="number">10 </span>{
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<span class="kw">let </span><span class="kw-2">mut </span>lock = my_count.lock().<span class="kw">await</span>;
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<span class="kw-2">*</span>lock += <span class="number">1</span>;
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<span class="macro">println!</span>(<span class="string">"{} {} {}"</span>, i, j, lock);
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}
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});
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}
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<span class="kw">loop </span>{
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<span class="kw">if </span><span class="kw-2">*</span>count.lock().<span class="kw">await </span>>= <span class="number">50 </span>{
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<span class="kw">break</span>;
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}
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}
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<span class="macro">println!</span>(<span class="string">"Count hit 50."</span>);</code></pre></div>
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<p>There are a few things of note here to pay attention to in this example.</p>
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<ol>
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<li>The mutex is wrapped in an <a href="https://doc.rust-lang.org/1.93.1/alloc/sync/struct.Arc.html" title="struct alloc::sync::Arc"><code>Arc</code></a> to allow it to be shared across
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threads.</li>
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<li>Each spawned task obtains a lock and releases it on every iteration.</li>
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<li>Mutation of the data protected by the Mutex is done by de-referencing
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the obtained lock as seen on lines 13 and 20.</li>
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</ol>
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<p>Tokio’s Mutex works in a simple FIFO (first in, first out) style where all
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calls to <a href="struct.Mutex.html#method.lock" title="method tokio::sync::Mutex::lock"><code>lock</code></a> complete in the order they were performed. In that way the
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Mutex is “fair” and predictable in how it distributes the locks to inner
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data. Locks are released and reacquired after every iteration, so basically,
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each thread goes to the back of the line after it increments the value once.
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Note that there’s some unpredictability to the timing between when the
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threads are started, but once they are going they alternate predictably.
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Finally, since there is only a single valid lock at any given time, there is
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no possibility of a race condition when mutating the inner value.</p>
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<p>Note that in contrast to <a href="https://doc.rust-lang.org/1.93.1/std/sync/poison/mutex/struct.Mutex.html" title="struct std::sync::poison::mutex::Mutex"><code>std::sync::Mutex</code></a>, this implementation does not
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poison the mutex when a thread holding the <a href="struct.MutexGuard.html" title="struct tokio::sync::MutexGuard"><code>MutexGuard</code></a> panics. In such a
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case, the mutex will be unlocked. If the panic is caught, this might leave
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the data protected by the mutex in an inconsistent state.</p>
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</div></details><h2 id="implementations" class="section-header">Implementations<a href="#implementations" class="anchor">§</a></h2><div id="implementations-list"><details class="toggle implementors-toggle" open><summary><section id="impl-Mutex%3CT%3E" class="impl"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#327-793">Source</a><a href="#impl-Mutex%3CT%3E" class="anchor">§</a><h3 class="code-header">impl<T: ?<a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> <a class="struct" href="struct.Mutex.html" title="struct tokio::sync::Mutex">Mutex</a><T></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.new" class="method"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#338-375">Source</a><h4 class="code-header">pub fn <a href="#method.new" class="fn">new</a>(t: T) -> Self<div class="where">where
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T: <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><div class="docblock"><p>Creates a new lock in an unlocked state ready for use.</p>
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<h5 id="examples-1"><a class="doc-anchor" href="#examples-1">§</a>Examples</h5>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::Mutex;
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<span class="kw">let </span>lock = Mutex::new(<span class="number">5</span>);</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.const_new" class="method"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#395-405">Source</a><h4 class="code-header">pub const fn <a href="#method.const_new" class="fn">const_new</a>(t: T) -> Self<div class="where">where
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T: <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><div class="docblock"><p>Creates a new lock in an unlocked state ready for use.</p>
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<p>When using the <code>tracing</code> <a href="../index.html#unstable-features" title="mod tokio">unstable feature</a>, a <code>Mutex</code> created with
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<code>const_new</code> will not be instrumented. As such, it will not be visible
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in <a href="https://github.com/tokio-rs/console"><code>tokio-console</code></a>. Instead, <a href="struct.Mutex.html#method.new" title="associated function tokio::sync::Mutex::new"><code>Mutex::new</code></a> should be used to create
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an instrumented object if that is needed.</p>
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<h5 id="examples-2"><a class="doc-anchor" href="#examples-2">§</a>Examples</h5>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::Mutex;
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<span class="kw">static </span>LOCK: Mutex<i32> = Mutex::const_new(<span class="number">5</span>);</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.lock" class="method"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#434-466">Source</a><h4 class="code-header">pub async fn <a href="#method.lock" class="fn">lock</a>(&self) -> <a class="struct" href="struct.MutexGuard.html" title="struct tokio::sync::MutexGuard">MutexGuard</a><'_, T></h4></section></summary><div class="docblock"><p>Locks this mutex, causing the current task to yield until the lock has
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been acquired. When the lock has been acquired, function returns a
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<a href="struct.MutexGuard.html" title="struct tokio::sync::MutexGuard"><code>MutexGuard</code></a>.</p>
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<p>If the mutex is available to be acquired immediately, then this call
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will typically not yield to the runtime. However, this is not guaranteed
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under all circumstances.</p>
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<h5 id="cancel-safety"><a class="doc-anchor" href="#cancel-safety">§</a>Cancel safety</h5>
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<p>This method uses a queue to fairly distribute locks in the order they
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were requested. Cancelling a call to <code>lock</code> makes you lose your place in
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the queue.</p>
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<h5 id="examples-3"><a class="doc-anchor" href="#examples-3">§</a>Examples</h5>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::Mutex;
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<span class="kw">let </span>mutex = Mutex::new(<span class="number">1</span>);
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<span class="kw">let </span><span class="kw-2">mut </span>n = mutex.lock().<span class="kw">await</span>;
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<span class="kw-2">*</span>n = <span class="number">2</span>;</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.blocking_lock" class="method"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#520-522">Source</a><h4 class="code-header">pub fn <a href="#method.blocking_lock" class="fn">blocking_lock</a>(&self) -> <a class="struct" href="struct.MutexGuard.html" title="struct tokio::sync::MutexGuard">MutexGuard</a><'_, T></h4></section></summary><div class="docblock"><p>Blockingly locks this <code>Mutex</code>. When the lock has been acquired, function returns a
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<a href="struct.MutexGuard.html" title="struct tokio::sync::MutexGuard"><code>MutexGuard</code></a>.</p>
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<p>This method is intended for use cases where you
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need to use this mutex in asynchronous code as well as in synchronous code.</p>
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<h5 id="panics"><a class="doc-anchor" href="#panics">§</a>Panics</h5>
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<p>This function panics if called within an asynchronous execution context.</p>
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<ul>
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<li>If you find yourself in an asynchronous execution context and needing
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to call some (synchronous) function which performs one of these
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<code>blocking_</code> operations, then consider wrapping that call inside
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<a href="../runtime/struct.Handle.html#method.spawn_blocking" title="method tokio::runtime::Handle::spawn_blocking"><code>spawn_blocking()</code></a>
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(or <a href="../task/fn.block_in_place.html" title="fn tokio::task::block_in_place"><code>block_in_place()</code></a>).</li>
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</ul>
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<h5 id="examples-4"><a class="doc-anchor" href="#examples-4">§</a>Examples</h5>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>std::sync::Arc;
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<span class="kw">use </span>tokio::sync::Mutex;
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<span class="attr">#[tokio::main]
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</span><span class="kw">async fn </span>main() {
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<span class="kw">let </span>mutex = Arc::new(Mutex::new(<span class="number">1</span>));
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<span class="kw">let </span>lock = mutex.lock().<span class="kw">await</span>;
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<span class="kw">let </span>mutex1 = Arc::clone(<span class="kw-2">&</span>mutex);
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<span class="kw">let </span>blocking_task = tokio::task::spawn_blocking(<span class="kw">move </span>|| {
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<span class="comment">// This shall block until the `lock` is released.
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</span><span class="kw">let </span><span class="kw-2">mut </span>n = mutex1.blocking_lock();
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<span class="kw-2">*</span>n = <span class="number">2</span>;
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});
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<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>lock, <span class="number">1</span>);
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<span class="comment">// Release the lock.
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</span>drop(lock);
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<span class="comment">// Await the completion of the blocking task.
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</span>blocking_task.<span class="kw">await</span>.unwrap();
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<span class="comment">// Assert uncontended.
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</span><span class="kw">let </span>n = mutex.try_lock().unwrap();
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<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>n, <span class="number">2</span>);
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}</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.blocking_lock_owned" class="method"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#578-580">Source</a><h4 class="code-header">pub fn <a href="#method.blocking_lock_owned" class="fn">blocking_lock_owned</a>(self: <a class="struct" href="https://doc.rust-lang.org/1.93.1/alloc/sync/struct.Arc.html" title="struct alloc::sync::Arc">Arc</a><Self>) -> <a class="struct" href="struct.OwnedMutexGuard.html" title="struct tokio::sync::OwnedMutexGuard">OwnedMutexGuard</a><T></h4></section></summary><div class="docblock"><p>Blockingly locks this <code>Mutex</code>. When the lock has been acquired, function returns an
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<a href="struct.OwnedMutexGuard.html" title="struct tokio::sync::OwnedMutexGuard"><code>OwnedMutexGuard</code></a>.</p>
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<p>This method is identical to <a href="struct.Mutex.html#method.blocking_lock" title="method tokio::sync::Mutex::blocking_lock"><code>Mutex::blocking_lock</code></a>, except that the returned
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guard references the <code>Mutex</code> with an <a href="https://doc.rust-lang.org/1.93.1/alloc/sync/struct.Arc.html" title="struct alloc::sync::Arc"><code>Arc</code></a> rather than by borrowing
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it. Therefore, the <code>Mutex</code> must be wrapped in an <code>Arc</code> to call this
|
||
method, and the guard will live for the <code>'static</code> lifetime, as it keeps
|
||
the <code>Mutex</code> alive by holding an <code>Arc</code>.</p>
|
||
<h5 id="panics-1"><a class="doc-anchor" href="#panics-1">§</a>Panics</h5>
|
||
<p>This function panics if called within an asynchronous execution context.</p>
|
||
<ul>
|
||
<li>If you find yourself in an asynchronous execution context and needing
|
||
to call some (synchronous) function which performs one of these
|
||
<code>blocking_</code> operations, then consider wrapping that call inside
|
||
<a href="../runtime/struct.Handle.html#method.spawn_blocking" title="method tokio::runtime::Handle::spawn_blocking"><code>spawn_blocking()</code></a>
|
||
(or <a href="../task/fn.block_in_place.html" title="fn tokio::task::block_in_place"><code>block_in_place()</code></a>).</li>
|
||
</ul>
|
||
<h5 id="examples-5"><a class="doc-anchor" href="#examples-5">§</a>Examples</h5>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>std::sync::Arc;
|
||
<span class="kw">use </span>tokio::sync::Mutex;
|
||
|
||
<span class="attr">#[tokio::main]
|
||
</span><span class="kw">async fn </span>main() {
|
||
<span class="kw">let </span>mutex = Arc::new(Mutex::new(<span class="number">1</span>));
|
||
<span class="kw">let </span>lock = mutex.lock().<span class="kw">await</span>;
|
||
|
||
<span class="kw">let </span>mutex1 = Arc::clone(<span class="kw-2">&</span>mutex);
|
||
<span class="kw">let </span>blocking_task = tokio::task::spawn_blocking(<span class="kw">move </span>|| {
|
||
<span class="comment">// This shall block until the `lock` is released.
|
||
</span><span class="kw">let </span><span class="kw-2">mut </span>n = mutex1.blocking_lock_owned();
|
||
<span class="kw-2">*</span>n = <span class="number">2</span>;
|
||
});
|
||
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>lock, <span class="number">1</span>);
|
||
<span class="comment">// Release the lock.
|
||
</span>drop(lock);
|
||
|
||
<span class="comment">// Await the completion of the blocking task.
|
||
</span>blocking_task.<span class="kw">await</span>.unwrap();
|
||
|
||
<span class="comment">// Assert uncontended.
|
||
</span><span class="kw">let </span>n = mutex.try_lock().unwrap();
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>n, <span class="number">2</span>);
|
||
}</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.lock_owned" class="method"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#618-653">Source</a><h4 class="code-header">pub async fn <a href="#method.lock_owned" class="fn">lock_owned</a>(self: <a class="struct" href="https://doc.rust-lang.org/1.93.1/alloc/sync/struct.Arc.html" title="struct alloc::sync::Arc">Arc</a><Self>) -> <a class="struct" href="struct.OwnedMutexGuard.html" title="struct tokio::sync::OwnedMutexGuard">OwnedMutexGuard</a><T></h4></section></summary><div class="docblock"><p>Locks this mutex, causing the current task to yield until the lock has
|
||
been acquired. When the lock has been acquired, this returns an
|
||
<a href="struct.OwnedMutexGuard.html" title="struct tokio::sync::OwnedMutexGuard"><code>OwnedMutexGuard</code></a>.</p>
|
||
<p>If the mutex is available to be acquired immediately, then this call
|
||
will typically not yield to the runtime. However, this is not guaranteed
|
||
under all circumstances.</p>
|
||
<p>This method is identical to <a href="struct.Mutex.html#method.lock" title="method tokio::sync::Mutex::lock"><code>Mutex::lock</code></a>, except that the returned
|
||
guard references the <code>Mutex</code> with an <a href="https://doc.rust-lang.org/1.93.1/alloc/sync/struct.Arc.html" title="struct alloc::sync::Arc"><code>Arc</code></a> rather than by borrowing
|
||
it. Therefore, the <code>Mutex</code> must be wrapped in an <code>Arc</code> to call this
|
||
method, and the guard will live for the <code>'static</code> lifetime, as it keeps
|
||
the <code>Mutex</code> alive by holding an <code>Arc</code>.</p>
|
||
<h5 id="cancel-safety-1"><a class="doc-anchor" href="#cancel-safety-1">§</a>Cancel safety</h5>
|
||
<p>This method uses a queue to fairly distribute locks in the order they
|
||
were requested. Cancelling a call to <code>lock_owned</code> makes you lose your
|
||
place in the queue.</p>
|
||
<h5 id="examples-6"><a class="doc-anchor" href="#examples-6">§</a>Examples</h5>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::Mutex;
|
||
<span class="kw">use </span>std::sync::Arc;
|
||
|
||
<span class="kw">let </span>mutex = Arc::new(Mutex::new(<span class="number">1</span>));
|
||
|
||
<span class="kw">let </span><span class="kw-2">mut </span>n = mutex.clone().lock_owned().<span class="kw">await</span>;
|
||
<span class="kw-2">*</span>n = <span class="number">2</span>;</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.try_lock" class="method"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#682-703">Source</a><h4 class="code-header">pub fn <a href="#method.try_lock" class="fn">try_lock</a>(&self) -> <a class="enum" href="https://doc.rust-lang.org/1.93.1/core/result/enum.Result.html" title="enum core::result::Result">Result</a><<a class="struct" href="struct.MutexGuard.html" title="struct tokio::sync::MutexGuard">MutexGuard</a><'_, T>, <a class="struct" href="struct.TryLockError.html" title="struct tokio::sync::TryLockError">TryLockError</a>></h4></section></summary><div class="docblock"><p>Attempts to acquire the lock, and returns <a href="struct.TryLockError.html" title="struct tokio::sync::TryLockError"><code>TryLockError</code></a> if the
|
||
lock is currently held somewhere else.</p>
|
||
<h5 id="examples-7"><a class="doc-anchor" href="#examples-7">§</a>Examples</h5>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::Mutex;
|
||
|
||
<span class="kw">let </span>mutex = Mutex::new(<span class="number">1</span>);
|
||
|
||
<span class="kw">let </span>n = mutex.try_lock()<span class="question-mark">?</span>;
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>n, <span class="number">1</span>);</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.get_mut" class="method"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#722-724">Source</a><h4 class="code-header">pub fn <a href="#method.get_mut" class="fn">get_mut</a>(&mut self) -> <a class="primitive" href="https://doc.rust-lang.org/1.93.1/std/primitive.reference.html">&mut T</a></h4></section></summary><div class="docblock"><p>Returns a mutable reference to the underlying data.</p>
|
||
<p>Since this call borrows the <code>Mutex</code> mutably, no actual locking needs to
|
||
take place – the mutable borrow statically guarantees no locks exist.</p>
|
||
<h5 id="examples-8"><a class="doc-anchor" href="#examples-8">§</a>Examples</h5>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::Mutex;
|
||
|
||
<span class="kw">fn </span>main() {
|
||
<span class="kw">let </span><span class="kw-2">mut </span>mutex = Mutex::new(<span class="number">1</span>);
|
||
|
||
<span class="kw">let </span>n = mutex.get_mut();
|
||
<span class="kw-2">*</span>n = <span class="number">2</span>;
|
||
}</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.try_lock_owned" class="method"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#750-771">Source</a><h4 class="code-header">pub fn <a href="#method.try_lock_owned" class="fn">try_lock_owned</a>(
|
||
self: <a class="struct" href="https://doc.rust-lang.org/1.93.1/alloc/sync/struct.Arc.html" title="struct alloc::sync::Arc">Arc</a><Self>,
|
||
) -> <a class="enum" href="https://doc.rust-lang.org/1.93.1/core/result/enum.Result.html" title="enum core::result::Result">Result</a><<a class="struct" href="struct.OwnedMutexGuard.html" title="struct tokio::sync::OwnedMutexGuard">OwnedMutexGuard</a><T>, <a class="struct" href="struct.TryLockError.html" title="struct tokio::sync::TryLockError">TryLockError</a>></h4></section></summary><div class="docblock"><p>Attempts to acquire the lock, and returns <a href="struct.TryLockError.html" title="struct tokio::sync::TryLockError"><code>TryLockError</code></a> if the lock
|
||
is currently held somewhere else.</p>
|
||
<p>This method is identical to <a href="struct.Mutex.html#method.try_lock" title="method tokio::sync::Mutex::try_lock"><code>Mutex::try_lock</code></a>, except that the
|
||
returned guard references the <code>Mutex</code> with an <a href="https://doc.rust-lang.org/1.93.1/alloc/sync/struct.Arc.html" title="struct alloc::sync::Arc"><code>Arc</code></a> rather than by
|
||
borrowing it. Therefore, the <code>Mutex</code> must be wrapped in an <code>Arc</code> to call
|
||
this method, and the guard will live for the <code>'static</code> lifetime, as it
|
||
keeps the <code>Mutex</code> alive by holding an <code>Arc</code>.</p>
|
||
<h5 id="examples-9"><a class="doc-anchor" href="#examples-9">§</a>Examples</h5>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::Mutex;
|
||
<span class="kw">use </span>std::sync::Arc;
|
||
|
||
<span class="kw">let </span>mutex = Arc::new(Mutex::new(<span class="number">1</span>));
|
||
|
||
<span class="kw">let </span>n = mutex.clone().try_lock_owned()<span class="question-mark">?</span>;
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>n, <span class="number">1</span>);</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.into_inner" class="method"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#787-792">Source</a><h4 class="code-header">pub fn <a href="#method.into_inner" class="fn">into_inner</a>(self) -> T<div class="where">where
|
||
T: <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><div class="docblock"><p>Consumes the mutex, returning the underlying data.</p>
|
||
<h5 id="examples-10"><a class="doc-anchor" href="#examples-10">§</a>Examples</h5>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::Mutex;
|
||
|
||
<span class="kw">let </span>mutex = Mutex::new(<span class="number">1</span>);
|
||
|
||
<span class="kw">let </span>n = mutex.into_inner();
|
||
<span class="macro">assert_eq!</span>(n, <span class="number">1</span>);</code></pre></div></div></details></div></details></div><h2 id="trait-implementations" class="section-header">Trait Implementations<a href="#trait-implementations" class="anchor">§</a></h2><div id="trait-implementations-list"><details class="toggle implementors-toggle" open><summary><section id="impl-Debug-for-Mutex%3CT%3E" class="impl"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#810-822">Source</a><a href="#impl-Debug-for-Mutex%3CT%3E" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> for <a class="struct" href="struct.Mutex.html" title="struct tokio::sync::Mutex">Mutex</a><T><div class="where">where
|
||
T: <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> + ?<a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.fmt" class="method trait-impl"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#814-821">Source</a><a href="#method.fmt" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.93.1/core/fmt/trait.Debug.html#tymethod.fmt" class="fn">fmt</a>(&self, f: &mut <a class="struct" href="https://doc.rust-lang.org/1.93.1/core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a><'_>) -> <a class="type" href="https://doc.rust-lang.org/1.93.1/core/fmt/type.Result.html" title="type core::fmt::Result">Result</a></h4></section></summary><div class='docblock'>Formats the value using the given formatter. <a href="https://doc.rust-lang.org/1.93.1/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-Default-for-Mutex%3CT%3E" class="impl"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#801-808">Source</a><a href="#impl-Default-for-Mutex%3CT%3E" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/default/trait.Default.html" title="trait core::default::Default">Default</a> for <a class="struct" href="struct.Mutex.html" title="struct tokio::sync::Mutex">Mutex</a><T><div class="where">where
|
||
T: <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/default/trait.Default.html" title="trait core::default::Default">Default</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.default" class="method trait-impl"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#805-807">Source</a><a href="#method.default" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.93.1/core/default/trait.Default.html#tymethod.default" class="fn">default</a>() -> Self</h4></section></summary><div class='docblock'>Returns the “default value” for a type. <a href="https://doc.rust-lang.org/1.93.1/core/default/trait.Default.html#tymethod.default">Read more</a></div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-From%3CT%3E-for-Mutex%3CT%3E" class="impl"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#795-799">Source</a><a href="#impl-From%3CT%3E-for-Mutex%3CT%3E" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.From.html" title="trait core::convert::From">From</a><T> for <a class="struct" href="struct.Mutex.html" title="struct tokio::sync::Mutex">Mutex</a><T></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from" class="method trait-impl"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#796-798">Source</a><a href="#method.from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.93.1/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(s: T) -> Self</h4></section></summary><div class='docblock'>Converts to this type from the input type.</div></details></div></details><section id="impl-Send-for-Mutex%3CT%3E" class="impl"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#258">Source</a><a href="#impl-Send-for-Mutex%3CT%3E" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> for <a class="struct" href="struct.Mutex.html" title="struct tokio::sync::Mutex">Mutex</a><T><div class="where">where
|
||
T: ?<a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a> + <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a>,</div></h3></section><section id="impl-Sync-for-Mutex%3CT%3E" class="impl"><a class="src rightside" href="../../src/tokio/sync/mutex.rs.html#259">Source</a><a href="#impl-Sync-for-Mutex%3CT%3E" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> for <a class="struct" href="struct.Mutex.html" title="struct tokio::sync::Mutex">Mutex</a><T><div class="where">where
|
||
T: ?<a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a> + <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a>,</div></h3></section></div><h2 id="synthetic-implementations" class="section-header">Auto Trait Implementations<a href="#synthetic-implementations" class="anchor">§</a></h2><div id="synthetic-implementations-list"><section id="impl-Freeze-for-Mutex%3CT%3E" class="impl"><a href="#impl-Freeze-for-Mutex%3CT%3E" class="anchor">§</a><h3 class="code-header">impl<T> !<a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Freeze.html" title="trait core::marker::Freeze">Freeze</a> for <a class="struct" href="struct.Mutex.html" title="struct tokio::sync::Mutex">Mutex</a><T></h3></section><section id="impl-RefUnwindSafe-for-Mutex%3CT%3E" class="impl"><a href="#impl-RefUnwindSafe-for-Mutex%3CT%3E" class="anchor">§</a><h3 class="code-header">impl<T> !<a class="trait" href="https://doc.rust-lang.org/1.93.1/core/panic/unwind_safe/trait.RefUnwindSafe.html" title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a> for <a class="struct" href="struct.Mutex.html" title="struct tokio::sync::Mutex">Mutex</a><T></h3></section><section id="impl-Unpin-for-Mutex%3CT%3E" class="impl"><a href="#impl-Unpin-for-Mutex%3CT%3E" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Unpin.html" title="trait core::marker::Unpin">Unpin</a> for <a class="struct" href="struct.Mutex.html" title="struct tokio::sync::Mutex">Mutex</a><T><div class="where">where
|
||
T: <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Unpin.html" title="trait core::marker::Unpin">Unpin</a> + ?<a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section><section id="impl-UnwindSafe-for-Mutex%3CT%3E" class="impl"><a href="#impl-UnwindSafe-for-Mutex%3CT%3E" class="anchor">§</a><h3 class="code-header">impl<T> !<a class="trait" href="https://doc.rust-lang.org/1.93.1/core/panic/unwind_safe/trait.UnwindSafe.html" title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a> for <a class="struct" href="struct.Mutex.html" title="struct tokio::sync::Mutex">Mutex</a><T></h3></section></div><h2 id="blanket-implementations" class="section-header">Blanket Implementations<a href="#blanket-implementations" class="anchor">§</a></h2><div id="blanket-implementations-list"><details class="toggle implementors-toggle"><summary><section id="impl-Any-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/any.rs.html#138">Source</a><a href="#impl-Any-for-T" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/any/trait.Any.html" title="trait core::any::Any">Any</a> for T<div class="where">where
|
||
T: 'static + ?<a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.type_id" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/any.rs.html#139">Source</a><a href="#method.type_id" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.93.1/core/any/trait.Any.html#tymethod.type_id" class="fn">type_id</a>(&self) -> <a class="struct" href="https://doc.rust-lang.org/1.93.1/core/any/struct.TypeId.html" title="struct core::any::TypeId">TypeId</a></h4></section></summary><div class='docblock'>Gets the <code>TypeId</code> of <code>self</code>. <a href="https://doc.rust-lang.org/1.93.1/core/any/trait.Any.html#tymethod.type_id">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-Borrow%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/borrow.rs.html#212">Source</a><a href="#impl-Borrow%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/borrow/trait.Borrow.html" title="trait core::borrow::Borrow">Borrow</a><T> for T<div class="where">where
|
||
T: ?<a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.borrow" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/borrow.rs.html#214">Source</a><a href="#method.borrow" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.93.1/core/borrow/trait.Borrow.html#tymethod.borrow" class="fn">borrow</a>(&self) -> <a class="primitive" href="https://doc.rust-lang.org/1.93.1/std/primitive.reference.html">&T</a></h4></section></summary><div class='docblock'>Immutably borrows from an owned value. <a href="https://doc.rust-lang.org/1.93.1/core/borrow/trait.Borrow.html#tymethod.borrow">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-BorrowMut%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/borrow.rs.html#221">Source</a><a href="#impl-BorrowMut%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/borrow/trait.BorrowMut.html" title="trait core::borrow::BorrowMut">BorrowMut</a><T> for T<div class="where">where
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T: ?<a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.borrow_mut" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/borrow.rs.html#222">Source</a><a href="#method.borrow_mut" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.93.1/core/borrow/trait.BorrowMut.html#tymethod.borrow_mut" class="fn">borrow_mut</a>(&mut self) -> <a class="primitive" href="https://doc.rust-lang.org/1.93.1/std/primitive.reference.html">&mut T</a></h4></section></summary><div class='docblock'>Mutably borrows from an owned value. <a href="https://doc.rust-lang.org/1.93.1/core/borrow/trait.BorrowMut.html#tymethod.borrow_mut">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-From%3C!%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/convert/mod.rs.html#802">Source</a><a href="#impl-From%3C!%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.From.html" title="trait core::convert::From">From</a><<a class="primitive" href="https://doc.rust-lang.org/1.93.1/std/primitive.never.html">!</a>> for T</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from-2" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/convert/mod.rs.html#803">Source</a><a href="#method.from-2" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.93.1/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(t: <a class="primitive" href="https://doc.rust-lang.org/1.93.1/std/primitive.never.html">!</a>) -> T</h4></section></summary><div class='docblock'>Converts to this type from the input type.</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-From%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/convert/mod.rs.html#785">Source</a><a href="#impl-From%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.From.html" title="trait core::convert::From">From</a><T> for T</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from-1" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/convert/mod.rs.html#788">Source</a><a href="#method.from-1" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.93.1/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(t: T) -> T</h4></section></summary><div class="docblock"><p>Returns the argument unchanged.</p>
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</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-Into%3CU%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/convert/mod.rs.html#767-769">Source</a><a href="#impl-Into%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T, U> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.Into.html" title="trait core::convert::Into">Into</a><U> for T<div class="where">where
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U: <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.From.html" title="trait core::convert::From">From</a><T>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.into" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/convert/mod.rs.html#777">Source</a><a href="#method.into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.93.1/core/convert/trait.Into.html#tymethod.into" class="fn">into</a>(self) -> U</h4></section></summary><div class="docblock"><p>Calls <code>U::from(self)</code>.</p>
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<p>That is, this conversion is whatever the implementation of
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<code><a href="https://doc.rust-lang.org/1.93.1/core/convert/trait.From.html" title="trait core::convert::From">From</a><T> for U</code> chooses to do.</p>
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</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-TryFrom%3CU%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/convert/mod.rs.html#827-829">Source</a><a href="#impl-TryFrom%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T, U> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a><U> for T<div class="where">where
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U: <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.Into.html" title="trait core::convert::Into">Into</a><T>,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Error-1" class="associatedtype trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/convert/mod.rs.html#831">Source</a><a href="#associatedtype.Error-1" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryFrom.html#associatedtype.Error" class="associatedtype">Error</a> = <a class="enum" href="https://doc.rust-lang.org/1.93.1/core/convert/enum.Infallible.html" title="enum core::convert::Infallible">Infallible</a></h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="toggle method-toggle" open><summary><section id="method.try_from" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/convert/mod.rs.html#834">Source</a><a href="#method.try_from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryFrom.html#tymethod.try_from" class="fn">try_from</a>(value: U) -> <a class="enum" href="https://doc.rust-lang.org/1.93.1/core/result/enum.Result.html" title="enum core::result::Result">Result</a><T, <T as <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a><U>>::<a class="associatedtype" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a>></h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-TryInto%3CU%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/convert/mod.rs.html#811-813">Source</a><a href="#impl-TryInto%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T, U> <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryInto.html" title="trait core::convert::TryInto">TryInto</a><U> for T<div class="where">where
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U: <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a><T>,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Error" class="associatedtype trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/convert/mod.rs.html#815">Source</a><a href="#associatedtype.Error" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryInto.html#associatedtype.Error" class="associatedtype">Error</a> = <U as <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a><T>>::<a class="associatedtype" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a></h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="toggle method-toggle" open><summary><section id="method.try_into" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.93.1/src/core/convert/mod.rs.html#818">Source</a><a href="#method.try_into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryInto.html#tymethod.try_into" class="fn">try_into</a>(self) -> <a class="enum" href="https://doc.rust-lang.org/1.93.1/core/result/enum.Result.html" title="enum core::result::Result">Result</a><U, <U as <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a><T>>::<a class="associatedtype" href="https://doc.rust-lang.org/1.93.1/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a>></h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details></div></section></div></main></body></html> |