| <!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="Thread-safe, non-blocking, “first one wins” flavor of `OnceCell`."><meta name="keywords" content="rust, rustlang, rust-lang, race"><title>once_cell::race - Rust</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../normalize.css"><link rel="stylesheet" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../ayu.css" disabled><link rel="stylesheet" href="../../dark.css" disabled><link rel="stylesheet" href="../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../storage.js"></script><script defer src="../../main.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../favicon.svg"></head><body class="rustdoc mod"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="mobile-topbar"><button class="sidebar-menu-toggle">☰</button><a class="sidebar-logo" href="../../once_cell/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a><h2></h2></nav><nav class="sidebar"><a class="sidebar-logo" href="../../once_cell/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a><h2 class="location"><a href="#">Module race</a></h2><div class="sidebar-elems"><section><ul class="block"><li><a href="#structs">Structs</a></li></ul></section></div></nav><main><div class="width-limiter"><nav class="sub"><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="main-heading"><h1 class="fqn">Module <a href="../index.html">once_cell</a>::<wbr><a class="mod" href="#">race</a><button id="copy-path" onclick="copy_path(this)" title="Copy item path to clipboard"><img src="../../clipboard.svg" width="19" height="18" alt="Copy item path"></button></h1><span class="out-of-band"><a class="srclink" href="../../src/once_cell/race.rs.html#1-419">source</a> · <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class="inner">−</span>]</a></span></div><details class="rustdoc-toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Thread-safe, non-blocking, “first one wins” flavor of <code>OnceCell</code>.</p> |
| <p>If two threads race to initialize a type from the <code>race</code> module, they |
| don’t block, execute initialization function together, but only one of |
| them stores the result.</p> |
| <p>This module does not require <code>std</code> feature.</p> |
| <h2 id="atomic-orderings"><a href="#atomic-orderings">Atomic orderings</a></h2> |
| <p>All types in this module use <code>Acquire</code> and <code>Release</code> |
| <a href="Ordering">atomic orderings</a> for all their operations. While this is not |
| strictly necessary for types other than <code>OnceBox</code>, it is useful for users as |
| it allows them to be certain that after <code>get</code> or <code>get_or_init</code> returns on |
| one thread, any side-effects caused by the setter thread prior to them |
| calling <code>set</code> or <code>get_or_init</code> will be made visible to that thread; without |
| it, it’s possible for it to appear as if they haven’t happened yet from the |
| getter thread’s perspective. This is an acceptable tradeoff to make since |
| <code>Acquire</code> and <code>Release</code> have very little performance overhead on most |
| architectures versus <code>Relaxed</code>.</p> |
| </div></details><h2 id="structs" class="small-section-header"><a href="#structs">Structs</a></h2><div class="item-table"><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.OnceBool.html" title="once_cell::race::OnceBool struct">OnceBool</a></div><div class="item-right docblock-short">A thread-safe cell which can be written to only once.</div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.OnceBox.html" title="once_cell::race::OnceBox struct">OnceBox</a></div><div class="item-right docblock-short">A thread-safe cell which can be written to only once.</div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.OnceNonZeroUsize.html" title="once_cell::race::OnceNonZeroUsize struct">OnceNonZeroUsize</a></div><div class="item-right docblock-short">A thread-safe cell which can be written to only once.</div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.OnceRef.html" title="once_cell::race::OnceRef struct">OnceRef</a></div><div class="item-right docblock-short">A thread-safe cell which can be written to only once.</div></div></div></section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="once_cell" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
