mirror of
https://github.com/OMGeeky/google-apis-rs.git
synced 2026-01-31 22:34:01 +01:00
24 lines
7.8 KiB
HTML
24 lines
7.8 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="Creates a future that is immediately ready with an Option of a value. Specifically this means that poll always returns Poll::Ready."><title>poll_immediate in futures_util::future - Rust</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/SourceSerif4-Regular-46f98efaafac5295.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/FiraSans-Regular-018c141bf0843ffd.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/FiraSans-Medium-8f9a781e4970d388.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2"><link rel="stylesheet" href="../../static.files/normalize-76eba96aa4d2e634.css"><link rel="stylesheet" href="../../static.files/rustdoc-ac92e1bbe349e143.css"><meta name="rustdoc-vars" data-root-path="../../" data-static-root-path="../../static.files/" data-current-crate="futures_util" data-themes="" data-resource-suffix="" data-rustdoc-version="1.76.0 (07dca489a 2024-02-04)" data-channel="1.76.0" data-search-js="search-2b6ce74ff89ae146.js" data-settings-js="settings-4313503d2e1961c2.js" ><script src="../../static.files/storage-f2adc0d6ca4d09fb.js"></script><script defer src="sidebar-items.js"></script><script defer src="../../static.files/main-305769736d49e732.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-feafe1bb7466e4bd.css"></noscript><link rel="alternate icon" type="image/png" href="../../static.files/favicon-16x16-8b506e7a72182f1c.png"><link rel="alternate icon" type="image/png" href="../../static.files/favicon-32x32-422f7d1d52889060.png"><link rel="icon" type="image/svg+xml" href="../../static.files/favicon-2c020d218678b618.svg"></head><body class="rustdoc fn"><!--[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></nav><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../futures_util/index.html">futures_util</a><span class="version">0.3.28</span></h2></div><div class="sidebar-elems"><h2><a href="index.html">In futures_util::future</a></h2></div></nav><div class="sidebar-resizer"></div>
|
||
<main><div class="width-limiter"><nav class="sub"><form class="search-form"><span></span><div id="sidebar-button" tabindex="-1"><a href="../../futures_util/all.html" title="show sidebar"></a></div><input class="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"><div id="help-button" tabindex="-1"><a href="../../help.html" title="help">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../static.files/wheel-7b819b6101059cd0.svg"></a></div></form></nav><section id="main-content" class="content"><div class="main-heading"><h1>Function <a href="../index.html">futures_util</a>::<wbr><a href="index.html">future</a>::<wbr><a class="fn" href="#">poll_immediate</a><button id="copy-path" title="Copy item path to clipboard"><img src="../../static.files/clipboard-7571035ce49a181d.svg" width="19" height="18" alt="Copy item path"></button></h1><span class="out-of-band"><a class="src" href="../../src/futures_util/future/poll_immediate.rs.html#124-126">source</a> · <button id="toggle-all-docs" title="collapse all docs">[<span>−</span>]</button></span></div><pre class="rust item-decl"><code>pub fn poll_immediate<F: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/future/future/trait.Future.html" title="trait core::future::future::Future">Future</a>>(f: F) -> <a class="struct" href="struct.PollImmediate.html" title="struct futures_util::future::PollImmediate">PollImmediate</a><F> <a href="#" class="tooltip" data-notable-ty="PollImmediate<F>">ⓘ</a></code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Creates a future that is immediately ready with an Option of a value.
|
||
Specifically this means that <a href="https://doc.rust-lang.org/1.76.0/core/future/future/trait.Future.html#tymethod.poll" title="method core::future::future::Future::poll">poll</a> always returns <a href="https://doc.rust-lang.org/1.76.0/core/task/poll/enum.Poll.html#variant.Ready" title="variant core::task::poll::Poll::Ready">Poll::Ready</a>.</p>
|
||
<h2 id="caution"><a href="#caution">Caution</a></h2>
|
||
<p>When consuming the future by this function, note the following:</p>
|
||
<ul>
|
||
<li>This function does not guarantee that the future will run to completion, so it is generally incompatible with passing the non-cancellation-safe future by value.</li>
|
||
<li>Even if the future is cancellation-safe, creating and dropping new futures frequently may lead to performance problems.</li>
|
||
</ul>
|
||
<h2 id="examples"><a href="#examples">Examples</a></h2>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>futures::future;
|
||
|
||
<span class="kw">let </span>r = future::poll_immediate(<span class="kw">async </span>{ <span class="number">1_u32 </span>});
|
||
<span class="macro">assert_eq!</span>(r.<span class="kw">await</span>, <span class="prelude-val">Some</span>(<span class="number">1</span>));
|
||
|
||
<span class="kw">let </span>p = future::poll_immediate(future::pending::<i32>());
|
||
<span class="macro">assert_eq!</span>(p.<span class="kw">await</span>, <span class="prelude-val">None</span>);</code></pre></div>
|
||
<h4 id="reusing-a-future"><a href="#reusing-a-future">Reusing a future</a></h4>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>futures::{future, pin_mut};
|
||
<span class="kw">let </span>f = <span class="kw">async </span>{<span class="macro">futures::pending!</span>(); <span class="number">42_u8</span>};
|
||
<span class="macro">pin_mut!</span>(f);
|
||
<span class="macro">assert_eq!</span>(<span class="prelude-val">None</span>, future::poll_immediate(<span class="kw-2">&mut </span>f).<span class="kw">await</span>);
|
||
<span class="macro">assert_eq!</span>(<span class="number">42</span>, f.<span class="kw">await</span>);</code></pre></div>
|
||
</div></details><script type="text/json" id="notable-traits-data">{"PollImmediate<F>":"<h3>Notable traits for <code><a class=\"struct\" href=\"struct.PollImmediate.html\" title=\"struct futures_util::future::PollImmediate\">PollImmediate</a><F></code></h3><pre><code><div class=\"where\">impl<T, F> <a class=\"trait\" href=\"https://doc.rust-lang.org/1.76.0/core/future/future/trait.Future.html\" title=\"trait core::future::future::Future\">Future</a> for <a class=\"struct\" href=\"struct.PollImmediate.html\" title=\"struct futures_util::future::PollImmediate\">PollImmediate</a><F><div class=\"where\">where\n F: <a class=\"trait\" href=\"https://doc.rust-lang.org/1.76.0/core/future/future/trait.Future.html\" title=\"trait core::future::future::Future\">Future</a><Output = T>,</div></div><div class=\"where\"> type <a href=\"https://doc.rust-lang.org/1.76.0/core/future/future/trait.Future.html#associatedtype.Output\" class=\"associatedtype\">Output</a> = <a class=\"enum\" href=\"https://doc.rust-lang.org/1.76.0/core/option/enum.Option.html\" title=\"enum core::option::Option\">Option</a><T>;</div>"}</script></section></div></main></body></html> |