367 lines
62 KiB
HTML
367 lines
62 KiB
HTML
<!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 reader-writer lock."><title>RwLock 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="#">RwLock</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="#">RwLock</a></h2><h3><a href="#">Sections</a></h3><ul class="block top-toc"><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_read" title="blocking_read">blocking_read</a></li><li><a href="#method.blocking_write" title="blocking_write">blocking_write</a></li><li><a href="#method.const_new" title="const_new">const_new</a></li><li><a href="#method.const_with_max_readers" title="const_with_max_readers">const_with_max_readers</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.new" title="new">new</a></li><li><a href="#method.read" title="read">read</a></li><li><a href="#method.read_owned" title="read_owned">read_owned</a></li><li><a href="#method.try_read" title="try_read">try_read</a></li><li><a href="#method.try_read_owned" title="try_read_owned">try_read_owned</a></li><li><a href="#method.try_write" title="try_write">try_write</a></li><li><a href="#method.try_write_owned" title="try_write_owned">try_write_owned</a></li><li><a href="#method.with_max_readers" title="with_max_readers">with_max_readers</a></li><li><a href="#method.write" title="write">write</a></li><li><a href="#method.write_owned" title="write_owned">write_owned</a></li></ul><h3><a href="#trait-implementations">Trait Implementations</a></h3><ul class="block trait-implementation"><li><a href="#impl-Debug-for-RwLock%3CT%3E" title="Debug">Debug</a></li><li><a href="#impl-Default-for-RwLock%3CT%3E" title="Default">Default</a></li><li><a href="#impl-From%3CT%3E-for-RwLock%3CT%3E" title="From<T>">From<T></a></li><li><a href="#impl-Send-for-RwLock%3CT%3E" title="Send">Send</a></li><li><a href="#impl-Sync-for-RwLock%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-RwLock%3CT%3E" title="!Freeze">!Freeze</a></li><li><a href="#impl-RefUnwindSafe-for-RwLock%3CT%3E" title="!RefUnwindSafe">!RefUnwindSafe</a></li><li><a href="#impl-UnwindSafe-for-RwLock%3CT%3E" title="!UnwindSafe">!UnwindSafe</a></li><li><a href="#impl-Unpin-for-RwLock%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">RwLock</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/rwlock.rs.html#88-100">Source</a> </span></div><pre class="rust item-decl"><code>pub struct RwLock<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 reader-writer lock.</p>
|
||
<p>This type of lock allows a number of readers or at most one writer at any
|
||
point in time. The write portion of this lock typically allows modification
|
||
of the underlying data (exclusive access) and the read portion of this lock
|
||
typically allows for read-only access (shared access).</p>
|
||
<p>In comparison, a <a href="struct.Mutex.html" title="struct tokio::sync::Mutex"><code>Mutex</code></a> does not distinguish between readers or writers
|
||
that acquire the lock, therefore causing any tasks waiting for the lock to
|
||
become available to yield. An <code>RwLock</code> will allow any number of readers to
|
||
acquire the lock as long as a writer is not holding the lock.</p>
|
||
<p>The priority policy of Tokio’s read-write lock is <em>fair</em> (or
|
||
<a href="https://en.wikipedia.org/wiki/Readers%E2%80%93writer_lock#Priority_policies"><em>write-preferring</em></a>), in order to ensure that readers cannot starve
|
||
writers. Fairness is ensured using a first-in, first-out queue for the tasks
|
||
awaiting the lock; if a task that wishes to acquire the write lock is at the
|
||
head of the queue, read locks will not be given out until the write lock has
|
||
been released. This is in contrast to the Rust standard library’s
|
||
<code>std::sync::RwLock</code>, where the priority policy is dependent on the
|
||
operating system’s implementation.</p>
|
||
<p>The type parameter <code>T</code> represents the data that this lock protects. It is
|
||
required that <code>T</code> satisfies <a href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Send.html" title="trait core::marker::Send"><code>Send</code></a> to be shared across threads. The RAII guards
|
||
returned from the locking methods implement <a href="https://doc.rust-lang.org/1.93.1/core/ops/deref/trait.Deref.html" title="trait core::ops::deref::Deref"><code>Deref</code></a>
|
||
(and <a href="https://doc.rust-lang.org/1.93.1/core/ops/deref/trait.DerefMut.html" title="trait core::ops::deref::DerefMut"><code>DerefMut</code></a>
|
||
for the <code>write</code> methods) to allow access to the content of the lock.</p>
|
||
<h2 id="examples"><a class="doc-anchor" href="#examples">§</a>Examples</h2>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::RwLock;
|
||
|
||
<span class="kw">let </span>lock = RwLock::new(<span class="number">5</span>);
|
||
|
||
<span class="comment">// many reader locks can be held at once
|
||
</span>{
|
||
<span class="kw">let </span>r1 = lock.read().<span class="kw">await</span>;
|
||
<span class="kw">let </span>r2 = lock.read().<span class="kw">await</span>;
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>r1, <span class="number">5</span>);
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>r2, <span class="number">5</span>);
|
||
} <span class="comment">// read locks are dropped at this point
|
||
|
||
// only one write lock may be held, however
|
||
</span>{
|
||
<span class="kw">let </span><span class="kw-2">mut </span>w = lock.write().<span class="kw">await</span>;
|
||
<span class="kw-2">*</span>w += <span class="number">1</span>;
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>w, <span class="number">6</span>);
|
||
} <span class="comment">// write lock is dropped here</span></code></pre></div></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-RwLock%3CT%3E" class="impl"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#193-1092">Source</a><a href="#impl-RwLock%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.RwLock.html" title="struct tokio::sync::RwLock">RwLock</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/rwlock.rs.html#204-254">Source</a><h4 class="code-header">pub fn <a href="#method.new" class="fn">new</a>(value: T) -> <a class="struct" href="struct.RwLock.html" title="struct tokio::sync::RwLock">RwLock</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>,</div></h4></section></summary><div class="docblock"><p>Creates a new instance of an <code>RwLock<T></code> which is unlocked.</p>
|
||
<h5 id="examples-1"><a class="doc-anchor" href="#examples-1">§</a>Examples</h5>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::RwLock;
|
||
|
||
<span class="kw">let </span>lock = RwLock::new(<span class="number">5</span>);</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.with_max_readers" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#271-327">Source</a><h4 class="code-header">pub fn <a href="#method.with_max_readers" class="fn">with_max_readers</a>(value: T, max_reads: <a class="primitive" href="https://doc.rust-lang.org/1.93.1/std/primitive.u32.html">u32</a>) -> <a class="struct" href="struct.RwLock.html" title="struct tokio::sync::RwLock">RwLock</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>,</div></h4></section></summary><div class="docblock"><p>Creates a new instance of an <code>RwLock<T></code> which is unlocked
|
||
and allows a maximum of <code>max_reads</code> concurrent readers.</p>
|
||
<h5 id="examples-2"><a class="doc-anchor" href="#examples-2">§</a>Examples</h5>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::RwLock;
|
||
|
||
<span class="kw">let </span>lock = RwLock::with_max_readers(<span class="number">5</span>, <span class="number">1024</span>);</code></pre></div><h5 id="panics"><a class="doc-anchor" href="#panics">§</a>Panics</h5>
|
||
<p>Panics if <code>max_reads</code> is more than <code>u32::MAX >> 3</code>.</p>
|
||
</div></details><details class="toggle method-toggle" open><summary><section id="method.const_new" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#347-358">Source</a><h4 class="code-header">pub const fn <a href="#method.const_new" class="fn">const_new</a>(value: T) -> <a class="struct" href="struct.RwLock.html" title="struct tokio::sync::RwLock">RwLock</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>,</div></h4></section></summary><div class="docblock"><p>Creates a new instance of an <code>RwLock<T></code> which is unlocked.</p>
|
||
<p>When using the <code>tracing</code> <a href="../index.html#unstable-features" title="mod tokio">unstable feature</a>, a <code>RwLock</code> created with
|
||
<code>const_new</code> will not be instrumented. As such, it will not be visible
|
||
in <a href="https://github.com/tokio-rs/console"><code>tokio-console</code></a>. Instead, <a href="struct.RwLock.html#method.new" title="associated function tokio::sync::RwLock::new"><code>RwLock::new</code></a> should be used to create
|
||
an instrumented object if that is needed.</p>
|
||
<h5 id="examples-3"><a class="doc-anchor" href="#examples-3">§</a>Examples</h5>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::RwLock;
|
||
|
||
<span class="kw">static </span>LOCK: RwLock<i32> = RwLock::const_new(<span class="number">5</span>);</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.const_with_max_readers" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#371-384">Source</a><h4 class="code-header">pub const fn <a href="#method.const_with_max_readers" class="fn">const_with_max_readers</a>(value: T, max_reads: <a class="primitive" href="https://doc.rust-lang.org/1.93.1/std/primitive.u32.html">u32</a>) -> <a class="struct" href="struct.RwLock.html" title="struct tokio::sync::RwLock">RwLock</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>,</div></h4></section></summary><div class="docblock"><p>Creates a new instance of an <code>RwLock<T></code> which is unlocked
|
||
and allows a maximum of <code>max_reads</code> concurrent readers.</p>
|
||
<h5 id="examples-4"><a class="doc-anchor" href="#examples-4">§</a>Examples</h5>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::RwLock;
|
||
|
||
<span class="kw">static </span>LOCK: RwLock<i32> = RwLock::const_with_max_readers(<span class="number">5</span>, <span class="number">1024</span>);</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.read" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#431-470">Source</a><h4 class="code-header">pub async fn <a href="#method.read" class="fn">read</a>(&self) -> <a class="struct" href="struct.RwLockReadGuard.html" title="struct tokio::sync::RwLockReadGuard">RwLockReadGuard</a><'_, T></h4></section></summary><div class="docblock"><p>Locks this <code>RwLock</code> with shared read access, causing the current task
|
||
to yield until the lock has been acquired.</p>
|
||
<p>The calling task will yield until there are no writers which hold the
|
||
lock. There may be other readers inside the lock when the task resumes.</p>
|
||
<p>Note that under the priority policy of <a href="struct.RwLock.html" title="struct tokio::sync::RwLock"><code>RwLock</code></a>, read locks are not
|
||
granted until prior write locks, to prevent starvation. Therefore
|
||
deadlock may occur if a read lock is held by the current task, a write
|
||
lock attempt is made, and then a subsequent read lock attempt is made
|
||
by the current task.</p>
|
||
<p>Returns an RAII guard which will drop this read access of the <code>RwLock</code>
|
||
when dropped.</p>
|
||
<h5 id="cancel-safety"><a class="doc-anchor" href="#cancel-safety">§</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>read</code> makes you lose your place in
|
||
the queue.</p>
|
||
<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::RwLock;
|
||
|
||
<span class="kw">let </span>lock = Arc::new(RwLock::new(<span class="number">1</span>));
|
||
<span class="kw">let </span>c_lock = lock.clone();
|
||
|
||
<span class="kw">let </span>n = lock.read().<span class="kw">await</span>;
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>n, <span class="number">1</span>);
|
||
|
||
tokio::spawn(<span class="kw">async move </span>{
|
||
<span class="comment">// While main has an active read lock, we acquire one too.
|
||
</span><span class="kw">let </span>r = c_lock.read().<span class="kw">await</span>;
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>r, <span class="number">1</span>);
|
||
}).<span class="kw">await</span>.expect(<span class="string">"The spawned task has panicked"</span>);
|
||
|
||
<span class="comment">// Drop the guard after the spawned task finishes.
|
||
</span>drop(n);</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.blocking_read" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#524-526">Source</a><h4 class="code-header">pub fn <a href="#method.blocking_read" class="fn">blocking_read</a>(&self) -> <a class="struct" href="struct.RwLockReadGuard.html" title="struct tokio::sync::RwLockReadGuard">RwLockReadGuard</a><'_, T></h4></section></summary><div class="docblock"><p>Blockingly locks this <code>RwLock</code> with shared read access.</p>
|
||
<p>This method is intended for use cases where you
|
||
need to use this rwlock in asynchronous code as well as in synchronous code.</p>
|
||
<p>Returns an RAII guard which will drop the read access of this <code>RwLock</code> when dropped.</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-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>std::sync::Arc;
|
||
<span class="kw">use </span>tokio::sync::RwLock;
|
||
|
||
<span class="attr">#[tokio::main]
|
||
</span><span class="kw">async fn </span>main() {
|
||
<span class="kw">let </span>rwlock = Arc::new(RwLock::new(<span class="number">1</span>));
|
||
<span class="kw">let </span><span class="kw-2">mut </span>write_lock = rwlock.write().<span class="kw">await</span>;
|
||
|
||
<span class="kw">let </span>blocking_task = tokio::task::spawn_blocking({
|
||
<span class="kw">let </span>rwlock = Arc::clone(<span class="kw-2">&</span>rwlock);
|
||
<span class="kw">move </span>|| {
|
||
<span class="comment">// This shall block until the `write_lock` is released.
|
||
</span><span class="kw">let </span>read_lock = rwlock.blocking_read();
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>read_lock, <span class="number">0</span>);
|
||
}
|
||
});
|
||
|
||
<span class="kw-2">*</span>write_lock -= <span class="number">1</span>;
|
||
drop(write_lock); <span class="comment">// release the lock.
|
||
|
||
// Await the completion of the blocking task.
|
||
</span>blocking_task.<span class="kw">await</span>.unwrap();
|
||
|
||
<span class="comment">// Assert uncontended.
|
||
</span><span class="macro">assert!</span>(rwlock.try_write().is_ok());
|
||
}</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.read_owned" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#579-621">Source</a><h4 class="code-header">pub async fn <a href="#method.read_owned" class="fn">read_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.OwnedRwLockReadGuard.html" title="struct tokio::sync::OwnedRwLockReadGuard">OwnedRwLockReadGuard</a><T></h4></section></summary><div class="docblock"><p>Locks this <code>RwLock</code> with shared read access, causing the current task
|
||
to yield until the lock has been acquired.</p>
|
||
<p>The calling task will yield until there are no writers which hold the
|
||
lock. There may be other readers inside the lock when the task resumes.</p>
|
||
<p>This method is identical to <a href="struct.RwLock.html#method.read" title="method tokio::sync::RwLock::read"><code>RwLock::read</code></a>, except that the returned
|
||
guard references the <code>RwLock</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>RwLock</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>RwLock</code> alive by holding an <code>Arc</code>.</p>
|
||
<p>Note that under the priority policy of <a href="struct.RwLock.html" title="struct tokio::sync::RwLock"><code>RwLock</code></a>, read locks are not
|
||
granted until prior write locks, to prevent starvation. Therefore
|
||
deadlock may occur if a read lock is held by the current task, a write
|
||
lock attempt is made, and then a subsequent read lock attempt is made
|
||
by the current task.</p>
|
||
<p>Returns an RAII guard which will drop this read access of the <code>RwLock</code>
|
||
when dropped.</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>read_owned</code> makes you lose your
|
||
place in the queue.</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>std::sync::Arc;
|
||
<span class="kw">use </span>tokio::sync::RwLock;
|
||
|
||
<span class="kw">let </span>lock = Arc::new(RwLock::new(<span class="number">1</span>));
|
||
<span class="kw">let </span>c_lock = lock.clone();
|
||
|
||
<span class="kw">let </span>n = lock.read_owned().<span class="kw">await</span>;
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>n, <span class="number">1</span>);
|
||
|
||
tokio::spawn(<span class="kw">async move </span>{
|
||
<span class="comment">// While main has an active read lock, we acquire one too.
|
||
</span><span class="kw">let </span>r = c_lock.read_owned().<span class="kw">await</span>;
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>r, <span class="number">1</span>);
|
||
}).<span class="kw">await</span>.expect(<span class="string">"The spawned task has panicked"</span>);
|
||
|
||
<span class="comment">// Drop the guard after the spawned task finishes.
|
||
</span>drop(n);
|
||
}</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.try_read" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#655-680">Source</a><h4 class="code-header">pub fn <a href="#method.try_read" class="fn">try_read</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.RwLockReadGuard.html" title="struct tokio::sync::RwLockReadGuard">RwLockReadGuard</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 this <code>RwLock</code> with shared read access.</p>
|
||
<p>If the access couldn’t be acquired immediately, returns <a href="struct.TryLockError.html" title="struct tokio::sync::TryLockError"><code>TryLockError</code></a>.
|
||
Otherwise, an RAII guard is returned which will release read access
|
||
when dropped.</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>std::sync::Arc;
|
||
<span class="kw">use </span>tokio::sync::RwLock;
|
||
|
||
<span class="kw">let </span>lock = Arc::new(RwLock::new(<span class="number">1</span>));
|
||
<span class="kw">let </span>c_lock = lock.clone();
|
||
|
||
<span class="kw">let </span>v = lock.try_read().unwrap();
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>v, <span class="number">1</span>);
|
||
|
||
tokio::spawn(<span class="kw">async move </span>{
|
||
<span class="comment">// While main has an active read lock, we acquire one too.
|
||
</span><span class="kw">let </span>n = c_lock.read().<span class="kw">await</span>;
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>n, <span class="number">1</span>);
|
||
}).<span class="kw">await</span>.expect(<span class="string">"The spawned task has panicked"</span>);
|
||
|
||
<span class="comment">// Drop the guard when spawned task finishes.
|
||
</span>drop(v);</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.try_read_owned" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#720-745">Source</a><h4 class="code-header">pub fn <a href="#method.try_read_owned" class="fn">try_read_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.OwnedRwLockReadGuard.html" title="struct tokio::sync::OwnedRwLockReadGuard">OwnedRwLockReadGuard</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 this <code>RwLock</code> with shared read access.</p>
|
||
<p>If the access couldn’t be acquired immediately, returns <a href="struct.TryLockError.html" title="struct tokio::sync::TryLockError"><code>TryLockError</code></a>.
|
||
Otherwise, an RAII guard is returned which will release read access
|
||
when dropped.</p>
|
||
<p>This method is identical to <a href="struct.RwLock.html#method.try_read" title="method tokio::sync::RwLock::try_read"><code>RwLock::try_read</code></a>, except that the
|
||
returned guard references the <code>RwLock</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>RwLock</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>RwLock</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>std::sync::Arc;
|
||
<span class="kw">use </span>tokio::sync::RwLock;
|
||
|
||
<span class="kw">let </span>lock = Arc::new(RwLock::new(<span class="number">1</span>));
|
||
<span class="kw">let </span>c_lock = lock.clone();
|
||
|
||
<span class="kw">let </span>v = lock.try_read_owned().unwrap();
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>v, <span class="number">1</span>);
|
||
|
||
tokio::spawn(<span class="kw">async move </span>{
|
||
<span class="comment">// While main has an active read lock, we acquire one too.
|
||
</span><span class="kw">let </span>n = c_lock.read_owned().<span class="kw">await</span>;
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>n, <span class="number">1</span>);
|
||
}).<span class="kw">await</span>.expect(<span class="string">"The spawned task has panicked"</span>);
|
||
|
||
<span class="comment">// Drop the guard when spawned task finishes.
|
||
</span>drop(v);</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.write" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#775-815">Source</a><h4 class="code-header">pub async fn <a href="#method.write" class="fn">write</a>(&self) -> <a class="struct" href="struct.RwLockWriteGuard.html" title="struct tokio::sync::RwLockWriteGuard">RwLockWriteGuard</a><'_, T></h4></section></summary><div class="docblock"><p>Locks this <code>RwLock</code> with exclusive write access, causing the current
|
||
task to yield until the lock has been acquired.</p>
|
||
<p>The calling task will yield while other writers or readers currently
|
||
have access to the lock.</p>
|
||
<p>Returns an RAII guard which will drop the write access of this <code>RwLock</code>
|
||
when dropped.</p>
|
||
<h5 id="cancel-safety-2"><a class="doc-anchor" href="#cancel-safety-2">§</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>write</code> makes you lose your place
|
||
in the queue.</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::RwLock;
|
||
|
||
<span class="kw">let </span>lock = RwLock::new(<span class="number">1</span>);
|
||
|
||
<span class="kw">let </span><span class="kw-2">mut </span>n = lock.write().<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.blocking_write" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#871-873">Source</a><h4 class="code-header">pub fn <a href="#method.blocking_write" class="fn">blocking_write</a>(&self) -> <a class="struct" href="struct.RwLockWriteGuard.html" title="struct tokio::sync::RwLockWriteGuard">RwLockWriteGuard</a><'_, T></h4></section></summary><div class="docblock"><p>Blockingly locks this <code>RwLock</code> with exclusive write access.</p>
|
||
<p>This method is intended for use cases where you
|
||
need to use this rwlock in asynchronous code as well as in synchronous code.</p>
|
||
<p>Returns an RAII guard which will drop the write access of this <code>RwLock</code> when dropped.</p>
|
||
<h5 id="panics-2"><a class="doc-anchor" href="#panics-2">§</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-11"><a class="doc-anchor" href="#examples-11">§</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::RwLock};
|
||
|
||
<span class="attr">#[tokio::main]
|
||
</span><span class="kw">async fn </span>main() {
|
||
<span class="kw">let </span>rwlock = Arc::new(RwLock::new(<span class="number">1</span>));
|
||
<span class="kw">let </span>read_lock = rwlock.read().<span class="kw">await</span>;
|
||
|
||
<span class="kw">let </span>blocking_task = tokio::task::spawn_blocking({
|
||
<span class="kw">let </span>rwlock = Arc::clone(<span class="kw-2">&</span>rwlock);
|
||
<span class="kw">move </span>|| {
|
||
<span class="comment">// This shall block until the `read_lock` is released.
|
||
</span><span class="kw">let </span><span class="kw-2">mut </span>write_lock = rwlock.blocking_write();
|
||
<span class="kw-2">*</span>write_lock = <span class="number">2</span>;
|
||
}
|
||
});
|
||
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>read_lock, <span class="number">1</span>);
|
||
<span class="comment">// Release the last outstanding read lock.
|
||
</span>drop(read_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>read_lock = rwlock.try_read().unwrap();
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>read_lock, <span class="number">2</span>);
|
||
}</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.write_owned" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#910-953">Source</a><h4 class="code-header">pub async fn <a href="#method.write_owned" class="fn">write_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.OwnedRwLockWriteGuard.html" title="struct tokio::sync::OwnedRwLockWriteGuard">OwnedRwLockWriteGuard</a><T></h4></section></summary><div class="docblock"><p>Locks this <code>RwLock</code> with exclusive write access, causing the current
|
||
task to yield until the lock has been acquired.</p>
|
||
<p>The calling task will yield while other writers or readers currently
|
||
have access to the lock.</p>
|
||
<p>This method is identical to <a href="struct.RwLock.html#method.write" title="method tokio::sync::RwLock::write"><code>RwLock::write</code></a>, except that the returned
|
||
guard references the <code>RwLock</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>RwLock</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>RwLock</code> alive by holding an <code>Arc</code>.</p>
|
||
<p>Returns an RAII guard which will drop the write access of this <code>RwLock</code>
|
||
when dropped.</p>
|
||
<h5 id="cancel-safety-3"><a class="doc-anchor" href="#cancel-safety-3">§</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>write_owned</code> makes you lose your
|
||
place in the queue.</p>
|
||
<h5 id="examples-12"><a class="doc-anchor" href="#examples-12">§</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::RwLock;
|
||
|
||
<span class="kw">let </span>lock = Arc::new(RwLock::new(<span class="number">1</span>));
|
||
|
||
<span class="kw">let </span><span class="kw-2">mut </span>n = lock.write_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_write" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#978-1004">Source</a><h4 class="code-header">pub fn <a href="#method.try_write" class="fn">try_write</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.RwLockWriteGuard.html" title="struct tokio::sync::RwLockWriteGuard">RwLockWriteGuard</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 this <code>RwLock</code> with exclusive write access.</p>
|
||
<p>If the access couldn’t be acquired immediately, returns <a href="struct.TryLockError.html" title="struct tokio::sync::TryLockError"><code>TryLockError</code></a>.
|
||
Otherwise, an RAII guard is returned which will release write access
|
||
when dropped.</p>
|
||
<h5 id="examples-13"><a class="doc-anchor" href="#examples-13">§</a>Examples</h5>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::RwLock;
|
||
|
||
<span class="kw">let </span>rw = RwLock::new(<span class="number">1</span>);
|
||
|
||
<span class="kw">let </span>v = rw.read().<span class="kw">await</span>;
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>v, <span class="number">1</span>);
|
||
|
||
<span class="macro">assert!</span>(rw.try_write().is_err());</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.try_write_owned" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#1036-1062">Source</a><h4 class="code-header">pub fn <a href="#method.try_write_owned" class="fn">try_write_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.OwnedRwLockWriteGuard.html" title="struct tokio::sync::OwnedRwLockWriteGuard">OwnedRwLockWriteGuard</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 this <code>RwLock</code> with exclusive write access.</p>
|
||
<p>If the access couldn’t be acquired immediately, returns <a href="struct.TryLockError.html" title="struct tokio::sync::TryLockError"><code>TryLockError</code></a>.
|
||
Otherwise, an RAII guard is returned which will release write access
|
||
when dropped.</p>
|
||
<p>This method is identical to <a href="struct.RwLock.html#method.try_write" title="method tokio::sync::RwLock::try_write"><code>RwLock::try_write</code></a>, except that the
|
||
returned guard references the <code>RwLock</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>RwLock</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>RwLock</code> alive by holding an <code>Arc</code>.</p>
|
||
<h5 id="examples-14"><a class="doc-anchor" href="#examples-14">§</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::RwLock;
|
||
|
||
<span class="kw">let </span>rw = Arc::new(RwLock::new(<span class="number">1</span>));
|
||
|
||
<span class="kw">let </span>v = Arc::clone(<span class="kw-2">&</span>rw).read_owned().<span class="kw">await</span>;
|
||
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>v, <span class="number">1</span>);
|
||
|
||
<span class="macro">assert!</span>(rw.try_write_owned().is_err());</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/rwlock.rs.html#1081-1083">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>RwLock</code> mutably, no actual locking needs to
|
||
take place – the mutable borrow statically guarantees no locks exist.</p>
|
||
<h5 id="examples-15"><a class="doc-anchor" href="#examples-15">§</a>Examples</h5>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>tokio::sync::RwLock;
|
||
|
||
<span class="kw">fn </span>main() {
|
||
<span class="kw">let </span><span class="kw-2">mut </span>lock = RwLock::new(<span class="number">1</span>);
|
||
|
||
<span class="kw">let </span>n = lock.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.into_inner" class="method"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#1086-1091">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 lock, returning the underlying data.</p>
|
||
</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-RwLock%3CT%3E" class="impl"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#1109-1121">Source</a><a href="#impl-Debug-for-RwLock%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.RwLock.html" title="struct tokio::sync::RwLock">RwLock</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/rwlock.rs.html#1113-1120">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-RwLock%3CT%3E" class="impl"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#1100-1107">Source</a><a href="#impl-Default-for-RwLock%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.RwLock.html" title="struct tokio::sync::RwLock">RwLock</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/rwlock.rs.html#1104-1106">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-RwLock%3CT%3E" class="impl"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#1094-1098">Source</a><a href="#impl-From%3CT%3E-for-RwLock%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.RwLock.html" title="struct tokio::sync::RwLock">RwLock</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/rwlock.rs.html#1095-1097">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-RwLock%3CT%3E" class="impl"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#149">Source</a><a href="#impl-Send-for-RwLock%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.RwLock.html" title="struct tokio::sync::RwLock">RwLock</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-RwLock%3CT%3E" class="impl"><a class="src rightside" href="../../src/tokio/sync/rwlock.rs.html#150">Source</a><a href="#impl-Sync-for-RwLock%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.RwLock.html" title="struct tokio::sync::RwLock">RwLock</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> + <a class="trait" href="https://doc.rust-lang.org/1.93.1/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</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-RwLock%3CT%3E" class="impl"><a href="#impl-Freeze-for-RwLock%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.RwLock.html" title="struct tokio::sync::RwLock">RwLock</a><T></h3></section><section id="impl-RefUnwindSafe-for-RwLock%3CT%3E" class="impl"><a href="#impl-RefUnwindSafe-for-RwLock%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.RwLock.html" title="struct tokio::sync::RwLock">RwLock</a><T></h3></section><section id="impl-Unpin-for-RwLock%3CT%3E" class="impl"><a href="#impl-Unpin-for-RwLock%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.RwLock.html" title="struct tokio::sync::RwLock">RwLock</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-RwLock%3CT%3E" class="impl"><a href="#impl-UnwindSafe-for-RwLock%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.RwLock.html" title="struct tokio::sync::RwLock">RwLock</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
|
||
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>
|
||
</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
|
||
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>
|
||
<p>That is, this conversion is whatever the implementation of
|
||
<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>
|
||
</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
|
||
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
|
||
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> |