31 lines
5.1 KiB
HTML
31 lines
5.1 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="Create an iterator running multiple iterators in lockstep."><title>izip in itertools - Rust</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-6b053e98.ttf.woff2,FiraSans-Regular-0fe48ade.woff2,FiraSans-Medium-e1aa3f0a.woff2,SourceCodePro-Regular-8badfe75.ttf.woff2,SourceCodePro-Semibold-aa29a496.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2" crossorigin href="../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../static.files/normalize-9960930a.css"><link rel="stylesheet" href="../static.files/rustdoc-42caa33d.css"><meta name="rustdoc-vars" data-root-path="../" data-static-root-path="../static.files/" data-current-crate="itertools" data-themes="" data-resource-suffix="" data-rustdoc-version="1.84.0 (9fc6b4312 2025-01-07)" data-channel="1.84.0" data-search-js="search-92e6798f.js" data-settings-js="settings-0f613d39.js" ><script src="../static.files/storage-59e33391.js"></script><script defer src="sidebar-items.js"></script><script defer src="../static.files/main-5f194d8c.js"></script><noscript><link rel="stylesheet" href="../static.files/noscript-893ab5e7.css"></noscript><link rel="alternate icon" type="image/png" href="../static.files/favicon-32x32-6580c154.png"><link rel="icon" type="image/svg+xml" href="../static.files/favicon-044be391.svg"></head><body class="rustdoc macro"><!--[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" title="show sidebar"></button></nav><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../itertools/index.html">itertools</a><span class="version">0.14.0</span></h2></div><div class="sidebar-elems"><div id="rustdoc-modnav"></div></div></nav><div class="sidebar-resizer"></div><main><div class="width-limiter"><rustdoc-search></rustdoc-search><section id="main-content" class="content"><div class="main-heading"><span class="rustdoc-breadcrumbs"><a href="index.html">itertools</a></span><h1>Macro <span class="macro">izip</span><button id="copy-path" title="Copy item path to clipboard">Copy item path</button></h1><rustdoc-toolbar></rustdoc-toolbar><span class="sub-heading"><a class="src" href="../src/itertools/lib.rs.html#321-360">Source</a> </span></div><pre class="rust item-decl"><code>macro_rules! izip {
|
||
( @closure $p:pat => $tup:expr ) => { ... };
|
||
( @closure $p:pat => ( $($tup:tt)* ) , $_iter:expr $( , $tail:expr )* ) => { ... };
|
||
($first:expr $(,)*) => { ... };
|
||
($first:expr, $second:expr $(,)*) => { ... };
|
||
( $first:expr $( , $rest:expr )* $(,)* ) => { ... };
|
||
}</code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Create an iterator running multiple iterators in lockstep.</p>
|
||
<p>The <code>izip!</code> iterator yields elements until any subiterator
|
||
returns <code>None</code>.</p>
|
||
<p>This is a version of the standard <code>.zip()</code> that’s supporting more than
|
||
two iterators. The iterator element type is a tuple with one element
|
||
from each of the input iterators. Just like <code>.zip()</code>, the iteration stops
|
||
when the shortest of the inputs reaches its end.</p>
|
||
<p><strong>Note:</strong> The result of this macro is in the general case an iterator
|
||
composed of repeated <code>.zip()</code> and a <code>.map()</code>; it has an anonymous type.
|
||
The special cases of one and two arguments produce the equivalent of
|
||
<code>$a.into_iter()</code> and <code>$a.into_iter().zip($b)</code> respectively.</p>
|
||
<p>Prefer this macro <code>izip!()</code> over <a href="fn.multizip.html" title="fn itertools::multizip"><code>multizip</code></a> for the performance benefits
|
||
of using the standard library <code>.zip()</code>.</p>
|
||
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered"><code>
|
||
<span class="comment">// iterate over three sequences side-by-side
|
||
</span><span class="kw">let </span><span class="kw-2">mut </span>results = [<span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>];
|
||
<span class="kw">let </span>inputs = [<span class="number">3</span>, <span class="number">7</span>, <span class="number">9</span>, <span class="number">6</span>];
|
||
|
||
<span class="kw">for </span>(r, index, input) <span class="kw">in </span><span class="macro">izip!</span>(<span class="kw-2">&mut </span>results, <span class="number">0</span>..<span class="number">10</span>, <span class="kw-2">&</span>inputs) {
|
||
<span class="kw-2">*</span>r = index * <span class="number">10 </span>+ input;
|
||
}
|
||
|
||
<span class="macro">assert_eq!</span>(results, [<span class="number">0 </span>+ <span class="number">3</span>, <span class="number">10 </span>+ <span class="number">7</span>, <span class="number">29</span>, <span class="number">36</span>]);</code></pre></div>
|
||
</div></details></section></div></main></body></html> |