mentat/scopeguard/struct.ScopeGuard.html

164 lines
15 KiB
HTML
Raw Normal View History

2018-08-22 17:04:13 +00:00
<!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 `ScopeGuard` struct in crate `scopeguard`.">
<meta name="keywords" content="rust, rustlang, rust-lang, ScopeGuard">
<title>scopeguard::ScopeGuard - 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="../main.css" id="themeStyle">
<script src="../storage.js"></script>
</head>
<body class="rustdoc struct">
<!--[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">&#9776;</div>
<p class='location'>Struct ScopeGuard</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#methods">Methods</a><div class="sidebar-links"><a href="#method.with_strategy">with_strategy</a></div><a class="sidebar-title" href="#implementations">Trait Implementations</a><div class="sidebar-links"><a href="#impl-Deref">Deref</a><a href="#impl-DerefMut">DerefMut</a><a href="#impl-Drop">Drop</a><a href="#impl-Debug">Debug</a></div></div><p class='location'><a href='index.html'>scopeguard</a></p><script>window.sidebarCurrent = {name: 'ScopeGuard', ty: 'struct', 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 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'>Struct <a href='index.html'>scopeguard</a>::<wbr><a class="struct" href=''>ScopeGuard</a></span><span class='out-of-band'><span id='render-detail'>
<a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">
[<span class='inner'>&#x2212;</span>]
</a>
</span><a class='srclink' href='../src/scopeguard/lib.rs.html#260-266' title='goto source code'>[src]</a></span></h1>
<pre class='rust struct'>pub struct ScopeGuard&lt;T, F, S:&nbsp;<a class="trait" href="../scopeguard/trait.Strategy.html" title="trait scopeguard::Strategy">Strategy</a>&nbsp;=&nbsp;<a class="enum" href="../scopeguard/enum.Always.html" title="enum scopeguard::Always">Always</a>&gt; <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;F: <a class="trait" href="https://doc.rust-lang.org/nightly/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(&amp;mut T),&nbsp;</span> { /* fields omitted */ }</pre><div class='docblock'><p><code>ScopeGuard</code> is a scope guard that may own a protected value.</p>
<p>If you place a guard in a local variable, the closure can
run regardless how you leave the scope — through regular return or panic
(except if panic or other code aborts; so as long as destructors run).
It is run only once.</p>
<p>The <code>S</code> parameter for <a href="Strategy.t.html"><code>Strategy</code></a> determines if
the closure actually runs.</p>
<p>The guard's closure will be called with a mut ref to the held value
in the destructor. It's called only once.</p>
<p>The <code>ScopeGuard</code> implements <code>Deref</code> so that you can access the inner value.</p>
</div>
<h2 id='methods' class='small-section-header'>
Methods<a href='#methods' class='anchor'></a>
</h2>
<h3 id='impl' class='impl'><span class='in-band'><code>impl&lt;T, F, S&gt; <a class="struct" href="../scopeguard/struct.ScopeGuard.html" title="struct scopeguard::ScopeGuard">ScopeGuard</a>&lt;T, F, S&gt; <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;F: <a class="trait" href="https://doc.rust-lang.org/nightly/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(&amp;mut T),<br>&nbsp;&nbsp;&nbsp;&nbsp;S: <a class="trait" href="../scopeguard/trait.Strategy.html" title="trait scopeguard::Strategy">Strategy</a>,&nbsp;</span></code><a href='#impl' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/scopeguard/lib.rs.html#267-283' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.with_strategy' class="method"><span id='with_strategy.v' class='invisible'><code>pub fn <a href='#method.with_strategy' class='fnname'>with_strategy</a>(v: T, dropfn: F) -&gt; <a class="struct" href="../scopeguard/struct.ScopeGuard.html" title="struct scopeguard::ScopeGuard">ScopeGuard</a>&lt;T, F, S&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/scopeguard/lib.rs.html#276-282' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Create a <code>ScopeGuard</code> that owns <code>v</code> (accessible through deref) and calls
<code>dropfn</code> when its destructor runs.</p>
<p>The <code>Strategy</code> decides whether the scope guard's closure should run.</p>
</div></div>
<h2 id='implementations' class='small-section-header'>
Trait Implementations<a href='#implementations' class='anchor'></a>
</h2>
<h3 id='impl-Deref' class='impl'><span class='in-band'><code>impl&lt;T, F, S:&nbsp;<a class="trait" href="../scopeguard/trait.Strategy.html" title="trait scopeguard::Strategy">Strategy</a>&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/ops/deref/trait.Deref.html" title="trait core::ops::deref::Deref">Deref</a> for <a class="struct" href="../scopeguard/struct.ScopeGuard.html" title="struct scopeguard::ScopeGuard">ScopeGuard</a>&lt;T, F, S&gt; <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;F: <a class="trait" href="https://doc.rust-lang.org/nightly/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(&amp;mut T),&nbsp;</span></code><a href='#impl-Deref' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/scopeguard/lib.rs.html#317-325' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='associatedtype.Target' class="type"><span id='Target.t' class='invisible'><code>type <a href='https://doc.rust-lang.org/nightly/core/ops/deref/trait.Deref.html#associatedtype.Target' class="type">Target</a> = T</code></span></h4>
<div class='docblock'><p>The resulting type after dereferencing.</p>
</div><h4 id='method.deref' class="method"><span id='deref.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/ops/deref/trait.Deref.html#tymethod.deref' class='fnname'>deref</a>(&amp;self) -&gt; &amp;T</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/scopeguard/lib.rs.html#321-323' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Dereferences the value.</p>
</div></div><h3 id='impl-DerefMut' class='impl'><span class='in-band'><code>impl&lt;T, F, S:&nbsp;<a class="trait" href="../scopeguard/trait.Strategy.html" title="trait scopeguard::Strategy">Strategy</a>&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/ops/deref/trait.DerefMut.html" title="trait core::ops::deref::DerefMut">DerefMut</a> for <a class="struct" href="../scopeguard/struct.ScopeGuard.html" title="struct scopeguard::ScopeGuard">ScopeGuard</a>&lt;T, F, S&gt; <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;F: <a class="trait" href="https://doc.rust-lang.org/nightly/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(&amp;mut T),&nbsp;</span></code><a href='#impl-DerefMut' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/scopeguard/lib.rs.html#327-333' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.deref_mut' class="method"><span id='deref_mut.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/ops/deref/trait.DerefMut.html#tymethod.deref_mut' class='fnname'>deref_mut</a>(&amp;mut self) -&gt; &amp;mut T</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/scopeguard/lib.rs.html#330-332' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Mutably dereferences the value.</p>
</div></div><h3 id='impl-Drop' class='impl'><span class='in-band'><code>impl&lt;T, F, S:&nbsp;<a class="trait" href="../scopeguard/trait.Strategy.html" title="trait scopeguard::Strategy">Strategy</a>&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/ops/drop/trait.Drop.html" title="trait core::ops::drop::Drop">Drop</a> for <a class="struct" href="../scopeguard/struct.ScopeGuard.html" title="struct scopeguard::ScopeGuard">ScopeGuard</a>&lt;T, F, S&gt; <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;F: <a class="trait" href="https://doc.rust-lang.org/nightly/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(&amp;mut T),&nbsp;</span></code><a href='#impl-Drop' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/scopeguard/lib.rs.html#335-343' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.drop' class="method"><span id='drop.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/ops/drop/trait.Drop.html#tymethod.drop' class='fnname'>drop</a>(&amp;mut self)</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/scopeguard/lib.rs.html#338-342' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Executes the destructor for this type. <a href="https://doc.rust-lang.org/nightly/core/ops/drop/trait.Drop.html#tymethod.drop">Read more</a></p>
</div></div><h3 id='impl-Debug' class='impl'><span class='in-band'><code>impl&lt;T, F, S&gt; <a class="trait" href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> for <a class="struct" href="../scopeguard/struct.ScopeGuard.html" title="struct scopeguard::ScopeGuard">ScopeGuard</a>&lt;T, F, S&gt; <span class="where fmt-newline">where<br>&nbsp;&nbsp;&nbsp;&nbsp;T: <a class="trait" href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a>,<br>&nbsp;&nbsp;&nbsp;&nbsp;F: <a class="trait" href="https://doc.rust-lang.org/nightly/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(&amp;mut T),<br>&nbsp;&nbsp;&nbsp;&nbsp;S: <a class="trait" href="../scopeguard/trait.Strategy.html" title="trait scopeguard::Strategy">Strategy</a> + <a class="trait" href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a>,&nbsp;</span></code><a href='#impl-Debug' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/scopeguard/lib.rs.html#345-355' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.fmt' class="method"><span id='fmt.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt' class='fnname'>fmt</a>(&amp;self, f: &amp;mut <a class="struct" href="https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a>) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/core/fmt/type.Result.html" title="type core::fmt::Result">Result</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/scopeguard/lib.rs.html#350-354' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Formats the value using the given formatter. <a href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></p>
</div></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><kbd>?</kbd></dt>
<dd>Show this help dialog</dd>
<dt><kbd>S</kbd></dt>
<dd>Focus the search field</dd>
<dt><kbd></kbd></dt>
<dd>Move up in search results</dd>
<dt><kbd></kbd></dt>
<dd>Move down in search results</dd>
<dt><kbd></kbd></dt>
<dd>Switch tab</dd>
<dt><kbd>&#9166;</kbd></dt>
<dd>Go to active search result</dd>
<dt><kbd>+</kbd></dt>
<dd>Expand all sections</dd>
<dt><kbd>-</kbd></dt>
<dd>Collapse 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 = "scopeguard";
</script>
<script src="../main.js"></script>
<script defer src="../search-index.js"></script>
</body>
</html>