<!DOCTYPE html><htmllang="en"><head><metacharset="utf-8"><metaname="viewport"content="width=device-width, initial-scale=1.0"><metaname="generator"content="rustdoc"><metaname="description"content="Wrapper around `ThreadLocal`."><title>CachedThreadLocal in thread_local - Rust</title><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../static.files/SourceSerif4-Regular-46f98efaafac5295.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../static.files/FiraSans-Regular-018c141bf0843ffd.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../static.files/FiraSans-Medium-8f9a781e4970d388.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../static.files/SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../static.files/SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2"><linkrel="stylesheet"href="../static.files/normalize-76eba96aa4d2e634.css"><linkrel="stylesheet"href="../static.files/rustdoc-5bc39a1768837dd0.css"><metaname="rustdoc-vars"data-root-path="../"data-static-root-path="../static.files/"data-current-crate="thread_local"data-themes=""data-resource-suffix=""data-rustdoc-version="1.77.0 (aedd173a2 2024-03-17)"data-channel="1.77.0"data-search-js="search-dd67cee4cfa65049.js"data-settings-js="settings-4313503d2e1961c2.js"><scriptsrc="../static.files/storage-4c98445ec4002617.js"></script><scriptdefersrc="sidebar-items.js"></script><scriptdefersrc="../static.files/main-48f368f3872407c8.js"></script><noscript><linkrel="stylesheet"href="../static.files/noscript-04d5337699b92874.css"></noscript><linkrel="alternate icon"type="image/png"href="../static.files/favicon-16x16-8b506e7a72182f1c.png"><linkrel="alternate icon"type="image/png"href="../static.files/favicon-32x32-422f7d1d52889060.png"><linkrel="icon"type="image/svg+xml"href="../static.files/favicon-2c020d218678b618.svg"></head><bodyclass="rustdoc struct"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><navclass="mobile-topbar"><buttonclass="sidebar-menu-toggle"title="show sidebar"></button></nav><navclass="sidebar"><divclass="sidebar-crate"><h2><ahref="../thread_local/index.html">thread_local</a><spanclass="version">1.1.8</span></h2></div><h2class="location"><ahref="#">CachedThreadLocal</a></h2><divclass="sidebar-elems"><section><h3><ahref="#implementations">Methods</a></h3><ulclass="block method"><li><ahref="#method.clear">clear</a></li><li><ahref="#method.get">get</a></li><li><ahref="#method.get_or">get_or</a></li><li><ahref="#method.get_or_default">get_or_default</a></li><li><ahref="#method.get_or_try">get_or_try</a></li><li><ahref="#method.iter_mut">iter_mut</a></li><li><ahref="#method.new">new</a></li></ul><h3><ahref="#trait-implementations">Trait Implementations</a></h3><ulclass="block trait-implementation"><li><ahref="#impl-Debug-for-CachedThreadLocal%3CT%3E">Debug</a></li><li><ahref="#impl-Default-for-CachedThreadLocal%3CT%3E">Default</a></li><li><ahref="#impl-IntoIterator-for-%26mut+CachedThreadLocal%3CT%3E">IntoIterator</a></li><li><ahref="#impl-IntoIterator-for-CachedThreadLocal%3CT%3E">IntoIterator</a></li><li><ahref="#impl-UnwindSafe-for-CachedThreadLocal%3CT%3E">UnwindSafe</a></li></ul><h3><ahref="#synthetic-implementations">Auto Trait Implementations</a></h3><ulclass="block synthetic-implementation"><li><ahref="#impl-RefUnwindSafe-for-CachedThreadLocal%3CT%3E">RefUnwindSafe</a></li><li><ahref="#impl-Send-for-CachedThreadLocal%3CT%3E">Send</a></li><li><ahref="#impl-Sync-for-CachedThreadLocal%3CT%3E">Sync</a></li><li><ahref="#impl-Unpin-for-CachedThreadLocal%3CT%3E">Unpin</a></li></ul><h3><ahref="#blanket-implementations">Blanket Implementations</a></h3><ulclass="block blanket-implementation"><li><ahref="#impl-Any-for-T">Any</a></li><li><ahref="#impl-Borrow%3CT%3E-for-T">Borrow<T></a></li><li><ahref="#impl-BorrowMut%3CT%3E-for-T">BorrowMut<T></
<main><divclass="width-limiter"><navclass="sub"><formclass="search-form"><span></span><divid="sidebar-button"tabindex="-1"><ahref="../thread_local/all.html"title="show sidebar"></a></div><inputclass="search-input"name="search"aria-label="Run search in the documentation"autocomplete="off"spellcheck="false"placeholder="Click or press ‘S’ to search, ‘?’ for more options…"type="search"><divid="help-button"tabindex="-1"><ahref="../help.html"title="help">?</a></div><divid="settings-menu"tabindex="-1"><ahref="../settings.html"title="settings"><imgwidth="22"height="22"alt="Change settings"src="../static.files/wheel-7b819b6101059cd0.svg"></a></div></form></nav><sectionid="main-content"class="content"><divclass="main-heading"><h1>Struct <ahref="index.html">thread_local</a>::<wbr><aclass="struct"href="#">CachedThreadLocal</a><buttonid="copy-path"title="Copy item path to clipboard"><imgsrc="../static.files/clipboard-7571035ce49a181d.svg"width="19"height="18"alt="Copy item path"></button></h1><spanclass="out-of-band"><aclass="src"href="../src/thread_local/cached.rs.html#13-15">source</a> · <buttonid="toggle-all-docs"title="collapse all docs">[<span>−</span>]</button></span></div><preclass="rust item-decl"><code>pub struct CachedThreadLocal<T: <aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/marker/trait.Send.html"title="trait core::marker::Send">Send</a>> { <spanclass="comment">/* private fields */</span> }</code></pre><spanclass="item-info"><divclass="stab deprecated"><spanclass="emoji">👎</span><span>Deprecated since 1.1.0: Use <code>ThreadLocal</code> instead</span></div></span><detailsclass="toggle top-doc"open><summaryclass="hideme"><span>Expand description</span></summary><divclass="docblock"><p>Wrapper around <ahref="struct.ThreadLocal.html"title="struct thread_local::ThreadLocal"><code>ThreadLocal</code></a>.</p>
<p>This used to add a fast path for a single thread, however that has been
obsoleted by performance improvements to <ahref="struct.ThreadLocal.html"title="struct thread_local::ThreadLocal"><code>ThreadLocal</code></a> itself.</p>
</div></details><h2id="implementations"class="section-header">Implementations<ahref="#implementations"class="anchor">§</a></h2><divid="implementations-list"><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-CachedThreadLocal%3CT%3E"class="impl"><aclass="src rightside"href="../src/thread_local/cached.rs.html#23-81">source</a><ahref="#impl-CachedThreadLocal%3CT%3E"class="anchor">§</a><h3class="code-header">impl<T: <aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/marker/trait.Send.html"title="trait core::marker::Send">Send</a>><aclass="struct"href="struct.CachedThreadLocal.html"title="struct thread_local::CachedThreadLocal">CachedThreadLocal</a><T></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.new"class="method"><aclass="src rightside"href="../src/thread_local/cached.rs.html#26-30">source</a><h4class="code-header">pub fn <ahref="#method.new"class="fn">new</a>() -><aclass="struct"href="struct.CachedThreadLocal.html"title="struct thread_local::CachedThreadLocal">CachedThreadLocal</a><T></h4></section></summary><divclass="docblock"><p>Creates a new empty <code>CachedThreadLocal</code>.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.get"class="method"><aclass="src rightside"href="../src/thread_local/cached.rs.html#34-36">source</a><h4class="code-header">pub fn <ahref="#method.get"class="fn">get</a>(&self) -><aclass="enum"href="https://doc.rust-lang.org/1.77.0/core/option/enum.Option.html"title="enum core::option::Option">Option</a><<aclass="primitive"href="https://doc.rust-lang.org/1.77.0/std/primitive.reference.html">&T</a>></h4></section></summary><divclass="docblock"><p>Returns the element for the current thread, if it exists.</p>
F: <aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/ops/function/trait.FnOnce.html"title="trait core::ops::function::FnOnce">FnOnce</a>() -> T,</div></h4></section></summary><divclass="docblock"><p>Returns the element for the current thread, or creates it if it doesn’t
F: <aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/ops/function/trait.FnOnce.html"title="trait core::ops::function::FnOnce">FnOnce</a>() -><aclass="enum"href="https://doc.rust-lang.org/1.77.0/core/result/enum.Result.html"title="enum core::result::Result">Result</a><T, E>,</div></h4></section></summary><divclass="docblock"><p>Returns the element for the current thread, or creates it if it doesn’t
exist. If <code>create</code> fails, that error is returned and no element is
added.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.iter_mut"class="method"><aclass="src rightside"href="../src/thread_local/cached.rs.html#65-69">source</a><h4class="code-header">pub fn <ahref="#method.iter_mut"class="fn">iter_mut</a>(&mut self) -><aclass="struct"href="struct.CachedIterMut.html"title="struct thread_local::CachedIterMut">CachedIterMut</a><'_, T><ahref="#"class="tooltip"data-notable-ty="CachedIterMut<'_, T>">ⓘ</a></h4></section></summary><divclass="docblock"><p>Returns a mutable iterator over the local values of all threads.</p>
<p>Since this call borrows the <code>ThreadLocal</code> mutably, this operation can
be done safely—the mutable borrow statically guarantees no other
threads are currently accessing their associated values.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.clear"class="method"><aclass="src rightside"href="../src/thread_local/cached.rs.html#78-80">source</a><h4class="code-header">pub fn <ahref="#method.clear"class="fn">clear</a>(&mut self)</h4></section></summary><divclass="docblock"><p>Removes all thread-specific values from the <code>ThreadLocal</code>, effectively
reseting it to its original state.</p>
<p>Since this call borrows the <code>ThreadLocal</code> mutably, this operation can
be done safely—the mutable borrow statically guarantees no other
threads are currently accessing their associated values.</p>
</div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-CachedThreadLocal%3CT%3E-1"class="impl"><aclass="src rightside"href="../src/thread_local/cached.rs.html#103-109">source</a><ahref="#impl-CachedThreadLocal%3CT%3E-1"class="anchor">§</a><h3class="code-header">impl<T: <aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/marker/trait.Send.html"title="trait core::marker::Send">Send</a> + <aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/default/trait.Default.html"title="trait core::default::Default">Default</a>><aclass="struct"href="struct.CachedThreadLocal.html"title="struct thread_local::CachedThreadLocal">CachedThreadLocal</a><T></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.get_or_default"class="method"><aclass="src rightside"href="../src/thread_local/cached.rs.html#106-108">source</a><h4class="code-header">pub fn <ahref="#method.get_or_default"class="fn">get_or_default</a>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/1.77.0/std/primitive.reference.html">&T</a></h4></section></summary><divclass="docblock"><p>Returns the element for the current thread, or creates a default one if
<code><ahref="https://doc.rust-lang.org/1.77.0/core/convert/trait.From.html"title="trait core::convert::From">From</a><T> for U</code> chooses to do.</p>
</div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-TryFrom%3CU%3E-for-T"class="impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.0/src/core/convert/mod.rs.html#804-806">source</a><ahref="#impl-TryFrom%3CU%3E-for-T"class="anchor">§</a><h3class="code-header">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><U> for T<divclass="where">where
U: <aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/convert/trait.Into.html"title="trait core::convert::Into">Into</a><T>,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle"open><summary><sectionid="associatedtype.Error-1"class="associatedtype trait-impl"><ahref="#associatedtype.Error-1"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryFrom.html#associatedtype.Error"class="associatedtype">Error</a> = <aclass="enum"href="https://doc.rust-lang.org/1.77.0/core/convert/enum.Infallible.html"title="enum core::convert::Infallible">Infallible</a></h4></section></summary><divclass='docblock'>The type returned in the event of a conversion error.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.try_from"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.0/src/core/convert/mod.rs.html#811">source</a><ahref="#method.try_from"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryFrom.html#tymethod.try_from"class="fn">try_from</a>(value: U) -><aclass="enum"href="https://doc.rust-lang.org/1.77.0/core/result/enum.Result.html"title="enum core::result::Result">Result</a><T, <T as <aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><U>>::<aclass="associatedtype"href="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a>></h4></section></summary><divclass='docblock'>Performs the conversion.</div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-TryInto%3CU%3E-for-T"class="impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.0/src/core/convert/mod.rs.html#789-791">source</a><ahref="#impl-TryInto%3CU%3E-for-T"class="anchor">§</a><h3class="code-header">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryInto.html"title="trait core::convert::TryInto">TryInto</a><U> for T<divclass="where">where
U: <aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle"open><summary><sectionid="associatedtype.Error"class="associatedtype trait-impl"><ahref="#associatedtype.Error"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryInto.html#associatedtype.Error"class="associatedtype">Error</a> = <U as <aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>>::<aclass="associatedtype"href="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a></h4></section></summary><divclass='docblock'>The type returned in the event of a conversion error.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.try_into"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.0/src/core/convert/mod.rs.html#796">source</a><ahref="#method.try_into"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryInto.html#tymethod.try_into"class="fn">try_into</a>(self) -><aclass="enum"href="https://doc.rust-lang.org/1.77.0/core/result/enum.Result.html"title="enum core::result::Result">Result</a><U, <U as <aclass="trait"href="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>>::<aclass="associatedtype"href="https://doc.rust-lang.org/1.77.0/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a>></h4></section></summary><divclass='docblock'>Performs the conversion.</div></details></div></details></div><scripttype="text/json"id="notable-traits-data">{"CachedIntoIter<T>":"<h3>Notabletraitsfor<code><aclass=\"struct\"href=\"struct.CachedIntoIter.html\"title=\"structthread_local::CachedIntoIter\">CachedIntoIter</a><T></code></h3><pre><code><divclass=\"where\">impl<T:<aclass=\"trait\"href=\"https://doc.rust-lang.org/1.77.0/core/marker/trait.Send.html\"title=\"traitcore::marker::Send\">Send</a>><aclass=\"trait\"href=\"https://doc.rust-lang.org/1.77.0/core/iter/traits/iterator/trait.Iterator.html\"title=\"traitcore::iter::traits::iterator::Iterator\">Iterator</a>for<aclass=\"struct\"href=\"struct.CachedIntoIter.html\"title=\"structthread_local::CachedIntoIter\">CachedIntoIter</a><T></div><divclass=\"where\">type<ahref=\"https://doc.rust-lang.org/1.77.0/core/iter/traits/iterator/trait.Iterator.html#associatedtype.Item\"class=\"associatedtype\">Item</a>=T;</div>","CachedIterMut<'_,T>":"<h3>Notabletraitsfor<code><aclass=\"struct\"href=\"struct.CachedIterMut.html\"title=\"structthread_local::CachedIterMut\">CachedIterMut</a><'a,T></code></h3><pre><code><divclass=\"where\">impl<'a,T:<aclass=\"trait\"href=\"https://doc.rust-lang.org/1.77.0/core/marker/trait.Send.html\"title=\"traitcore::marker::Send\">Send</a>+'a><aclass=\"trait\"href=\"https://doc.rust-lang.org/1.77.0/core/iter/traits/iterator/trait.Iterator.html\"title=\"traitcore::iter::traits::iterator::Iterator\">Iterator</a>for<aclass=\"struct\"href=\"struct.CachedIterMut.html\"title=\"structthread_local::CachedIterMut\">CachedIterMut</a><'a,T></div><divclass=\"where\">type<ahref=\"https://doc.rust-lang.org/1.77.0/core/iter/traits/iterator/trait.Iterator.html#associatedtype.Item\"class=\"associatedtype\">Item</a>=<aclass=\"primitive\"href=\"https://doc.rust-lang.org/1.77.0/std/primitive.reference.html\">&'amutT</a>;</div>","CachedIterMut<'a,T>":"<h3>Notabletraitsfor<code><aclass=\"struct\"href=\"struct.CachedIterMut.html\"title=\"structthread_local::CachedIterMut\">CachedIterMut</a><'a,T></code></h3><pr
