| <!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/git/checkouts/rayon-3b3b152053499ede/a07ce2e/src/iter/empty.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>empty.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="../../../rayon/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="../../../rayon/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> |
| <span id="2">2</span> |
| <span id="3">3</span> |
| <span id="4">4</span> |
| <span id="5">5</span> |
| <span id="6">6</span> |
| <span id="7">7</span> |
| <span id="8">8</span> |
| <span id="9">9</span> |
| <span id="10">10</span> |
| <span id="11">11</span> |
| <span id="12">12</span> |
| <span id="13">13</span> |
| <span id="14">14</span> |
| <span id="15">15</span> |
| <span id="16">16</span> |
| <span id="17">17</span> |
| <span id="18">18</span> |
| <span id="19">19</span> |
| <span id="20">20</span> |
| <span id="21">21</span> |
| <span id="22">22</span> |
| <span id="23">23</span> |
| <span id="24">24</span> |
| <span id="25">25</span> |
| <span id="26">26</span> |
| <span id="27">27</span> |
| <span id="28">28</span> |
| <span id="29">29</span> |
| <span id="30">30</span> |
| <span id="31">31</span> |
| <span id="32">32</span> |
| <span id="33">33</span> |
| <span id="34">34</span> |
| <span id="35">35</span> |
| <span id="36">36</span> |
| <span id="37">37</span> |
| <span id="38">38</span> |
| <span id="39">39</span> |
| <span id="40">40</span> |
| <span id="41">41</span> |
| <span id="42">42</span> |
| <span id="43">43</span> |
| <span id="44">44</span> |
| <span id="45">45</span> |
| <span id="46">46</span> |
| <span id="47">47</span> |
| <span id="48">48</span> |
| <span id="49">49</span> |
| <span id="50">50</span> |
| <span id="51">51</span> |
| <span id="52">52</span> |
| <span id="53">53</span> |
| <span id="54">54</span> |
| <span id="55">55</span> |
| <span id="56">56</span> |
| <span id="57">57</span> |
| <span id="58">58</span> |
| <span id="59">59</span> |
| <span id="60">60</span> |
| <span id="61">61</span> |
| <span id="62">62</span> |
| <span id="63">63</span> |
| <span id="64">64</span> |
| <span id="65">65</span> |
| <span id="66">66</span> |
| <span id="67">67</span> |
| <span id="68">68</span> |
| <span id="69">69</span> |
| <span id="70">70</span> |
| <span id="71">71</span> |
| <span id="72">72</span> |
| <span id="73">73</span> |
| <span id="74">74</span> |
| <span id="75">75</span> |
| <span id="76">76</span> |
| <span id="77">77</span> |
| <span id="78">78</span> |
| <span id="79">79</span> |
| <span id="80">80</span> |
| <span id="81">81</span> |
| <span id="82">82</span> |
| <span id="83">83</span> |
| <span id="84">84</span> |
| <span id="85">85</span> |
| <span id="86">86</span> |
| <span id="87">87</span> |
| <span id="88">88</span> |
| <span id="89">89</span> |
| <span id="90">90</span> |
| <span id="91">91</span> |
| <span id="92">92</span> |
| <span id="93">93</span> |
| <span id="94">94</span> |
| <span id="95">95</span> |
| <span id="96">96</span> |
| <span id="97">97</span> |
| <span id="98">98</span> |
| <span id="99">99</span> |
| <span id="100">100</span> |
| <span id="101">101</span> |
| <span id="102">102</span> |
| <span id="103">103</span> |
| <span id="104">104</span> |
| </pre><pre class="rust"><code><span class="kw">use </span><span class="kw">crate</span>::iter::plumbing::<span class="kw-2">*</span>; |
| <span class="kw">use </span><span class="kw">crate</span>::iter::<span class="kw-2">*</span>; |
| |
| <span class="kw">use </span>std::fmt; |
| <span class="kw">use </span>std::marker::PhantomData; |
| |
| <span class="doccomment">/// Creates a parallel iterator that produces nothing. |
| /// |
| /// This admits no parallelism on its own, but it could be used for code that |
| /// deals with generic parallel iterators. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// use rayon::prelude::*; |
| /// use rayon::iter::empty; |
| /// |
| /// let pi = (0..1234).into_par_iter() |
| /// .chain(empty()) |
| /// .chain(1234..10_000); |
| /// |
| /// assert_eq!(pi.count(), 10_000); |
| /// ``` |
| </span><span class="kw">pub fn </span>empty<T: Send>() -> Empty<T> { |
| Empty { |
| marker: PhantomData, |
| } |
| } |
| |
| <span class="doccomment">/// Iterator adaptor for [the `empty()` function](fn.empty.html). |
| </span><span class="kw">pub struct </span>Empty<T: Send> { |
| marker: PhantomData<T>, |
| } |
| |
| <span class="kw">impl</span><T: Send> Clone <span class="kw">for </span>Empty<T> { |
| <span class="kw">fn </span>clone(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="self">Self </span>{ |
| empty() |
| } |
| } |
| |
| <span class="kw">impl</span><T: Send> fmt::Debug <span class="kw">for </span>Empty<T> { |
| <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, f: <span class="kw-2">&mut </span>fmt::Formatter<<span class="lifetime">'_</span>>) -> fmt::Result { |
| f.pad(<span class="string">"Empty"</span>) |
| } |
| } |
| |
| <span class="kw">impl</span><T: Send> ParallelIterator <span class="kw">for </span>Empty<T> { |
| <span class="kw">type </span>Item = T; |
| |
| <span class="kw">fn </span>drive_unindexed<C>(<span class="self">self</span>, consumer: C) -> C::Result |
| <span class="kw">where |
| </span>C: UnindexedConsumer<<span class="self">Self</span>::Item>, |
| { |
| <span class="self">self</span>.drive(consumer) |
| } |
| |
| <span class="kw">fn </span>opt_len(<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: Send> IndexedParallelIterator <span class="kw">for </span>Empty<T> { |
| <span class="kw">fn </span>drive<C>(<span class="self">self</span>, consumer: C) -> C::Result |
| <span class="kw">where |
| </span>C: Consumer<<span class="self">Self</span>::Item>, |
| { |
| consumer.into_folder().complete() |
| } |
| |
| <span class="kw">fn </span>len(<span class="kw-2">&</span><span class="self">self</span>) -> usize { |
| <span class="number">0 |
| </span>} |
| |
| <span class="kw">fn </span>with_producer<CB>(<span class="self">self</span>, callback: CB) -> CB::Output |
| <span class="kw">where |
| </span>CB: ProducerCallback<<span class="self">Self</span>::Item>, |
| { |
| callback.callback(EmptyProducer(PhantomData)) |
| } |
| } |
| |
| <span class="doccomment">/// Private empty producer |
| </span><span class="kw">struct </span>EmptyProducer<T: Send>(PhantomData<T>); |
| |
| <span class="kw">impl</span><T: Send> Producer <span class="kw">for </span>EmptyProducer<T> { |
| <span class="kw">type </span>Item = T; |
| <span class="kw">type </span>IntoIter = std::iter::Empty<T>; |
| |
| <span class="kw">fn </span>into_iter(<span class="self">self</span>) -> <span class="self">Self</span>::IntoIter { |
| std::iter::empty() |
| } |
| |
| <span class="kw">fn </span>split_at(<span class="self">self</span>, index: usize) -> (<span class="self">Self</span>, <span class="self">Self</span>) { |
| <span class="macro">debug_assert_eq!</span>(index, <span class="number">0</span>); |
| (<span class="self">self</span>, EmptyProducer(PhantomData)) |
| } |
| |
| <span class="kw">fn </span>fold_with<F>(<span class="self">self</span>, folder: F) -> F |
| <span class="kw">where |
| </span>F: Folder<<span class="self">Self</span>::Item>, |
| { |
| folder |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="rayon" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |