38 lines
11 KiB
HTML
38 lines
11 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="API documentation for the Rust `BuildHasher` trait in crate `nom`."><meta name="keywords" content="rust, rustlang, rust-lang, BuildHasher"><title>nom::lib::std::hash::BuildHasher - Rust</title><link rel="stylesheet" type="text/css" href="../../../../normalize.css"><link rel="stylesheet" type="text/css" href="../../../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" type="text/css" href="../../../../dark.css"><link rel="stylesheet" type="text/css" href="../../../../light.css" id="themeStyle"><script src="../../../../storage.js"></script><noscript><link rel="stylesheet" href="../../../../noscript.css"></noscript><link rel="shortcut icon" href="../../../../favicon.ico"><style type="text/css">#crate-search{background-image:url("../../../../down-arrow.svg");}</style></head><body class="rustdoc trait"><!--[if lte IE 8]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="sidebar-menu">☰</div><a href='../../../../nom/index.html'><div class='logo-container'><img src='../../../../rust-logo.png' alt='logo'></div></a><p class='location'>Trait BuildHasher</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#associated-types">Associated Types</a><div class="sidebar-links"><a href="#associatedtype.Hasher">Hasher</a></div><a class="sidebar-title" href="#required-methods">Required Methods</a><div class="sidebar-links"><a href="#tymethod.build_hasher">build_hasher</a></div><a class="sidebar-title" href="#implementors">Implementors</a></div><p class='location'><a href='../../../index.html'>nom</a>::<wbr><a href='../../index.html'>lib</a>::<wbr><a href='../index.html'>std</a>::<wbr><a href='index.html'>hash</a></p><script>window.sidebarCurrent = {name: 'BuildHasher', ty: 'trait', relpath: ''};</script><script defer src="sidebar-items.js"></script></div></nav><div class="theme-picker"><button id="theme-picker" aria-label="Pick another theme!"><img src="../../../../brush.svg" width="18" alt="Pick another theme!"></button><div id="theme-choices"></div></div><script src="../../../../theme.js"></script><nav class="sub"><form class="search-form"><div class="search-container"><div><select id="crate-search"><option value="All crates">All crates</option></select><input class="search-input" name="search" disabled autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"></div><a id="settings-menu" href="../../../../settings.html"><img src="../../../../wheel.svg" width="18" alt="Change settings"></a></div></form></nav><section id="main" class="content"><h1 class='fqn'><span class='out-of-band'><span class='since' title='Stable since Rust version 1.7.0'>1.7.0</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='https://doc.rust-lang.org/nightly/src/core/hash/mod.rs.html#442-465' title='goto source code'>[src]</a></span><span class='in-band'>Trait <a href='../../../index.html'>nom</a>::<wbr><a href='../../index.html'>lib</a>::<wbr><a href='../index.html'>std</a>::<wbr><a href='index.html'>hash</a>::<wbr><a class="trait" href=''>BuildHasher</a></span></h1><div class="docblock type-decl hidden-by-usual-hider"><pre class='rust trait'>pub trait BuildHasher {
|
||
type <a href='#associatedtype.Hasher' class="type">Hasher</a>: <a class="trait" href="../../../../nom/lib/std/hash/trait.Hasher.html" title="trait nom::lib::std::hash::Hasher">Hasher</a>;
|
||
fn <a href='#tymethod.build_hasher' class='fnname'>build_hasher</a>(&self) -> Self::<a class="type" href="../../../../nom/lib/std/hash/trait.BuildHasher.html#associatedtype.Hasher" title="type nom::lib::std::hash::BuildHasher::Hasher">Hasher</a>;
|
||
}</pre></div><div class='docblock'><p>A trait for creating instances of <a href="trait.Hasher.html"><code>Hasher</code></a>.</p>
|
||
<p>A <code>BuildHasher</code> is typically used (e.g., by <a href="../../std/collections/struct.HashMap.html"><code>HashMap</code></a>) to create
|
||
<a href="trait.Hasher.html"><code>Hasher</code></a>s for each key such that they are hashed independently of one
|
||
another, since <a href="trait.Hasher.html"><code>Hasher</code></a>s contain state.</p>
|
||
<p>For each instance of <code>BuildHasher</code>, the <a href="trait.Hasher.html"><code>Hasher</code></a>s created by
|
||
<a href="#tymethod.build_hasher"><code>build_hasher</code></a> should be identical. That is, if the same stream of bytes
|
||
is fed into each hasher, the same output will also be generated.</p>
|
||
<h1 id="examples" class="section-header"><a href="#examples">Examples</a></h1>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered">
|
||
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">hash_map</span>::<span class="ident">RandomState</span>;
|
||
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">hash</span>::{<span class="ident">BuildHasher</span>, <span class="ident">Hasher</span>};
|
||
|
||
<span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">RandomState</span>::<span class="ident">new</span>();
|
||
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">hasher_1</span> <span class="op">=</span> <span class="ident">s</span>.<span class="ident">build_hasher</span>();
|
||
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">hasher_2</span> <span class="op">=</span> <span class="ident">s</span>.<span class="ident">build_hasher</span>();
|
||
|
||
<span class="ident">hasher_1</span>.<span class="ident">write_u32</span>(<span class="number">8128</span>);
|
||
<span class="ident">hasher_2</span>.<span class="ident">write_u32</span>(<span class="number">8128</span>);
|
||
|
||
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">hasher_1</span>.<span class="ident">finish</span>(), <span class="ident">hasher_2</span>.<span class="ident">finish</span>());</pre></div>
|
||
</div>
|
||
<h2 id='associated-types' class='small-section-header'>Associated Types<a href='#associated-types' class='anchor'></a></h2><div class='methods'><h3 id='associatedtype.Hasher' class='method'><code id='Hasher.t'>type <a href='#associatedtype.Hasher' class="type">Hasher</a>: <a class="trait" href="../../../../nom/lib/std/hash/trait.Hasher.html" title="trait nom::lib::std::hash::Hasher">Hasher</a></code></h3><div class='docblock'><p>Type of the hasher that will be created.</p>
|
||
</div></div><span class='loading-content'>Loading content...</span>
|
||
<h2 id='required-methods' class='small-section-header'>Required methods<a href='#required-methods' class='anchor'></a></h2><div class='methods'><h3 id='tymethod.build_hasher' class='method'><code id='build_hasher.v'>fn <a href='#tymethod.build_hasher' class='fnname'>build_hasher</a>(&self) -> Self::<a class="type" href="../../../../nom/lib/std/hash/trait.BuildHasher.html#associatedtype.Hasher" title="type nom::lib::std::hash::BuildHasher::Hasher">Hasher</a></code></h3><div class='docblock'><p>Creates a new hasher.</p>
|
||
<p>Each call to <code>build_hasher</code> on the same instance should produce identical
|
||
<a href="trait.Hasher.html"><code>Hasher</code></a>s.</p>
|
||
<h1 id="examples-1" class="section-header"><a href="#examples-1">Examples</a></h1>
|
||
<div class="example-wrap"><pre class="rust rust-example-rendered">
|
||
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">hash_map</span>::<span class="ident">RandomState</span>;
|
||
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">hash</span>::<span class="ident">BuildHasher</span>;
|
||
|
||
<span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">RandomState</span>::<span class="ident">new</span>();
|
||
<span class="kw">let</span> <span class="ident">new_s</span> <span class="op">=</span> <span class="ident">s</span>.<span class="ident">build_hasher</span>();</pre></div>
|
||
</div></div><span class='loading-content'>Loading content...</span>
|
||
<h2 id='implementors' class='small-section-header'>Implementors<a href='#implementors' class='anchor'></a></h2><div class='item-list' id='implementors-list'><h3 id='impl-BuildHasher' class='impl'><code class='in-band'>impl BuildHasher for <a class="struct" href="../../../../nom/lib/std/collections/hash_map/struct.RandomState.html" title="struct nom::lib::std::collections::hash_map::RandomState">RandomState</a></code><a href='#impl-BuildHasher' class='anchor'></a><a class='srclink' href='https://doc.rust-lang.org/nightly/src/std/collections/hash/map.rs.html#2470-2477' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='associatedtype.Hasher-1' class="type"><code id='Hasher.t-1'>type <a href='#associatedtype.Hasher-1' class="type">Hasher</a> = <a class="struct" href="../../../../nom/lib/std/collections/hash_map/struct.DefaultHasher.html" title="struct nom::lib::std::collections::hash_map::DefaultHasher">DefaultHasher</a></code></h4><h4 id='method.build_hasher' class="method hidden"><code id='build_hasher.v-1'>fn <a href='#method.build_hasher' class='fnname'>build_hasher</a>(&self) -> <a class="struct" href="../../../../nom/lib/std/collections/hash_map/struct.DefaultHasher.html" title="struct nom::lib::std::collections::hash_map::DefaultHasher">DefaultHasher</a></code><a class='srclink' href='https://doc.rust-lang.org/nightly/src/std/collections/hash/map.rs.html#2474-2476' title='goto source code'>[src]</a></h4></div><h3 id='impl-BuildHasher-1' class='impl'><code class='in-band'>impl<H> BuildHasher for <a class="struct" href="../../../../nom/lib/std/hash/struct.BuildHasherDefault.html" title="struct nom::lib::std::hash::BuildHasherDefault">BuildHasherDefault</a><H> <span class="where fmt-newline">where<br> H: <a class="trait" href="../../../../nom/lib/std/prelude/v1/v1/trait.Default.html" title="trait nom::lib::std::prelude::v1::v1::Default">Default</a> + <a class="trait" href="../../../../nom/lib/std/hash/trait.Hasher.html" title="trait nom::lib::std::hash::Hasher">Hasher</a>, </span></code><a href='#impl-BuildHasher-1' class='anchor'></a><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/hash/mod.rs.html#526-532' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='associatedtype.Hasher-2' class="type"><code id='Hasher.t-2'>type <a href='#associatedtype.Hasher-2' class="type">Hasher</a> = H</code></h4><h4 id='method.build_hasher-1' class="method hidden"><code id='build_hasher.v-2'>fn <a href='#method.build_hasher-1' class='fnname'>build_hasher</a>(&self) -> H</code><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/hash/mod.rs.html#529-531' title='goto source code'>[src]</a></h4></div></div><span class='loading-content'>Loading content...</span><script type="text/javascript" src="../../../../implementors/core/hash/trait.BuildHasher.js" async></script></section><section id="search" class="content hidden"></section><section class="footer"></section><script>window.rootPath = "../../../../";window.currentCrate = "nom";</script><script src="../../../../aliases.js"></script><script src="../../../../main.js"></script><script defer src="../../../../search-index.js"></script></body></html> |