<!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="API documentation for the Rust `from_utf8_unchecked` fn in crate `collections`."> <meta name="keywords" content="rust, rustlang, rust-lang, from_utf8_unchecked"> <title>collections::str::from_utf8_unchecked - Rust</title> <link rel="stylesheet" type="text/css" href="../../normalize.css"> <link rel="stylesheet" type="text/css" href="../../rustdoc.css"> <link rel="stylesheet" type="text/css" href="../../main.css"> <link rel="shortcut icon" href="https://doc.rust-lang.org/favicon.ico"> </head> <body class="rustdoc fn"> <!--[if lte IE 8]> <div class="warning"> This old browser is unsupported and will most likely display funky things. </div> <![endif]--> <nav class="sidebar"> <a href='../../collections/index.html'><img src='https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png' alt='logo' width='100'></a> <p class='location'><a href='../index.html'>collections</a>::<wbr><a href='index.html'>str</a></p><script>window.sidebarCurrent = {name: 'from_utf8_unchecked', ty: 'fn', relpath: ''};</script><script defer src="sidebar-items.js"></script> </nav> <nav class="sub"> <form class="search-form js-only"> <div class="search-container"> <input class="search-input" name="search" autocomplete="off" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"> </div> </form> </nav> <section id='main' class="content"> <h1 class='fqn'><span class='in-band'>Function <a href='../index.html'>collections</a>::<wbr><a href='index.html'>str</a>::<wbr><a class="fn" href=''>from_utf8_unchecked</a></span><span class='out-of-band'><span class='since' title='Stable since Rust version 1.0.0'>1.0.0</span><span id='render-detail'> <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs"> [<span class='inner'>−</span>] </a> </span><a class='srclink' href='../../src/core/str/mod.rs.html#374-376' title='goto source code'>[src]</a></span></h1> <pre class='rust fn'>pub unsafe fn from_utf8_unchecked(v: &[u8]) -> &str</pre><div class='docblock'><p>Converts a slice of bytes to a string slice without checking that the string contains valid UTF-8.</p> <p>See the safe version, <a href="fn.from_utf8.html"><code>from_utf8</code></a>, for more information.</p> <h1 id='safety' class='section-header'><a href='#safety'>Safety</a></h1> <p>This function is unsafe because it does not check that the bytes passed to it are valid UTF-8. If this constraint is violated, undefined behavior results, as the rest of Rust assumes that <a href="../../std/primitive.str.html"><code>&str</code></a>s are valid UTF-8.</p> <h1 id='examples' class='section-header'><a href='#examples'>Examples</a></h1> <p>Basic usage:</p> <pre class="rust rust-example-rendered"> <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">str</span>; <span class="comment">// some bytes, in a vector</span> <span class="kw">let</span> <span class="ident">sparkle_heart</span> <span class="op">=</span> <span class="macro">vec</span><span class="macro">!</span>[<span class="number">240</span>, <span class="number">159</span>, <span class="number">146</span>, <span class="number">150</span>]; <span class="kw">let</span> <span class="ident">sparkle_heart</span> <span class="op">=</span> <span class="kw">unsafe</span> { <span class="ident">str</span>::<span class="ident">from_utf8_unchecked</span>(<span class="kw-2">&</span><span class="ident">sparkle_heart</span>) }; <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="string">"💖"</span>, <span class="ident">sparkle_heart</span>);<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=fn%20main()%20%7B%0Ause%20std%3A%3Astr%3B%0A%0A%2F%2F%20some%20bytes%2C%20in%20a%20vector%0Alet%20sparkle_heart%20%3D%20vec!%5B240%2C%20159%2C%20146%2C%20150%5D%3B%0A%0Alet%20sparkle_heart%20%3D%20unsafe%20%7B%0A%20%20%20%20str%3A%3Afrom_utf8_unchecked(%26sparkle_heart)%0A%7D%3B%0A%0Aassert_eq!(%22%F0%9F%92%96%22%2C%20sparkle_heart)%3B%0A%7D">Run</a></pre> </div></section> <section id='search' class="content hidden"></section> <section class="footer"></section> <aside id="help" class="hidden"> <div> <h1 class="hidden">Help</h1> <div class="shortcuts"> <h2>Keyboard Shortcuts</h2> <dl> <dt>?</dt> <dd>Show this help dialog</dd> <dt>S</dt> <dd>Focus the search field</dd> <dt>⇤</dt> <dd>Move up in search results</dd> <dt>⇥</dt> <dd>Move down in search results</dd> <dt>⏎</dt> <dd>Go to active search result</dd> <dt>+</dt> <dd>Collapse/expand all sections</dd> </dl> </div> <div class="infos"> <h2>Search Tricks</h2> <p> Prefix searches with a type followed by a colon (e.g. <code>fn:</code>) to restrict the search to a given type. </p> <p> Accepted types are: <code>fn</code>, <code>mod</code>, <code>struct</code>, <code>enum</code>, <code>trait</code>, <code>type</code>, <code>macro</code>, and <code>const</code>. </p> <p> Search functions by type signature (e.g. <code>vec -> usize</code> or <code>* -> vec</code>) </p> </div> </div> </aside> <script> window.rootPath = "../../"; window.currentCrate = "collections"; </script> <script src="../../main.js"></script> <script defer src="../../search-index.js"></script> </body> </html>