| <!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="Source of the Rust file `/root/.cargo/registry/src/github.com-1ecc6299db9ec823/crossbeam-channel-0.5.8/src/flavors/never.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>never.rs - source</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="../../../source-script.js"></script><script defer src="../../../source-files.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 source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../../crossbeam_channel/index.html"><div class="logo-container"><img class="rust-logo" src="../../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../../crossbeam_channel/index.html"><img class="rust-logo" src="../../../rust-logo.svg" alt="logo"></a><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="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
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| </pre><pre class="rust"><code><span class="doccomment">//! Channel that never delivers messages. |
| //! |
| //! Messages cannot be sent into this kind of channel. |
| |
| </span><span class="kw">use </span>std::marker::PhantomData; |
| <span class="kw">use </span>std::time::Instant; |
| |
| <span class="kw">use </span><span class="kw">crate</span>::context::Context; |
| <span class="kw">use </span><span class="kw">crate</span>::err::{RecvTimeoutError, TryRecvError}; |
| <span class="kw">use </span><span class="kw">crate</span>::select::{Operation, SelectHandle, Token}; |
| <span class="kw">use </span><span class="kw">crate</span>::utils; |
| |
| <span class="doccomment">/// This flavor doesn't need a token. |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">type </span>NeverToken = (); |
| |
| <span class="doccomment">/// Channel that never delivers messages. |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>Channel<T> { |
| _marker: PhantomData<T>, |
| } |
| |
| <span class="kw">impl</span><T> Channel<T> { |
| <span class="doccomment">/// Creates a channel that never delivers messages. |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>new() -> <span class="self">Self </span>{ |
| Channel { |
| _marker: PhantomData, |
| } |
| } |
| |
| <span class="doccomment">/// Attempts to receive a message without blocking. |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>try_recv(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="prelude-ty">Result</span><T, TryRecvError> { |
| <span class="prelude-val">Err</span>(TryRecvError::Empty) |
| } |
| |
| <span class="doccomment">/// Receives a message from the channel. |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>recv(<span class="kw-2">&</span><span class="self">self</span>, deadline: <span class="prelude-ty">Option</span><Instant>) -> <span class="prelude-ty">Result</span><T, RecvTimeoutError> { |
| utils::sleep_until(deadline); |
| <span class="prelude-val">Err</span>(RecvTimeoutError::Timeout) |
| } |
| |
| <span class="doccomment">/// Reads a message from the channel. |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">unsafe fn </span>read(<span class="kw-2">&</span><span class="self">self</span>, _token: <span class="kw-2">&mut </span>Token) -> <span class="prelude-ty">Result</span><T, ()> { |
| <span class="prelude-val">Err</span>(()) |
| } |
| |
| <span class="doccomment">/// Returns `true` if the channel is empty. |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>is_empty(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="bool-val">true |
| </span>} |
| |
| <span class="doccomment">/// Returns `true` if the channel is full. |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>is_full(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="bool-val">true |
| </span>} |
| |
| <span class="doccomment">/// Returns the number of messages in the channel. |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>len(<span class="kw-2">&</span><span class="self">self</span>) -> usize { |
| <span class="number">0 |
| </span>} |
| |
| <span class="doccomment">/// Returns the capacity of the channel. |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>capacity(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="prelude-ty">Option</span><usize> { |
| <span class="prelude-val">Some</span>(<span class="number">0</span>) |
| } |
| } |
| |
| <span class="kw">impl</span><T> SelectHandle <span class="kw">for </span>Channel<T> { |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>try_select(<span class="kw-2">&</span><span class="self">self</span>, _token: <span class="kw-2">&mut </span>Token) -> bool { |
| <span class="bool-val">false |
| </span>} |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>deadline(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="prelude-ty">Option</span><Instant> { |
| <span class="prelude-val">None |
| </span>} |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>register(<span class="kw-2">&</span><span class="self">self</span>, _oper: Operation, _cx: <span class="kw-2">&</span>Context) -> bool { |
| <span class="self">self</span>.is_ready() |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>unregister(<span class="kw-2">&</span><span class="self">self</span>, _oper: Operation) {} |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>accept(<span class="kw-2">&</span><span class="self">self</span>, token: <span class="kw-2">&mut </span>Token, _cx: <span class="kw-2">&</span>Context) -> bool { |
| <span class="self">self</span>.try_select(token) |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>is_ready(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="bool-val">false |
| </span>} |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>watch(<span class="kw-2">&</span><span class="self">self</span>, _oper: Operation, _cx: <span class="kw-2">&</span>Context) -> bool { |
| <span class="self">self</span>.is_ready() |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>unwatch(<span class="kw-2">&</span><span class="self">self</span>, _oper: Operation) {} |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="crossbeam_channel" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
