|
|
<!DOCTYPE HTML>
|
|
|
<html lang="en">
|
|
|
<head>
|
|
|
<meta charset="UTF-8">
|
|
|
<title>注释 - Rust 程序设计语言 简体中文版</title>
|
|
|
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
|
|
|
<meta name="description" content="Rust 程序设计语言 简体中文版">
|
|
|
<meta name="viewport" content="width=device-width, initial-scale=1">
|
|
|
|
|
|
<base href="">
|
|
|
|
|
|
<link rel="stylesheet" href="book.css">
|
|
|
<link href='https://fonts.googleapis.com/css?family=Open+Sans:300italic,400italic,600italic,700italic,800italic,400,300,600,700,800' rel='stylesheet' type='text/css'>
|
|
|
|
|
|
<link rel="shortcut icon" href="favicon.png">
|
|
|
|
|
|
<!-- Font Awesome -->
|
|
|
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.3.0/css/font-awesome.min.css">
|
|
|
|
|
|
<link rel="stylesheet" href="highlight.css">
|
|
|
<link rel="stylesheet" href="tomorrow-night.css">
|
|
|
|
|
|
<!-- MathJax -->
|
|
|
<script type="text/javascript" src="https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
|
|
|
|
|
|
<!-- Fetch JQuery from CDN but have a local fallback -->
|
|
|
<script src="https://code.jquery.com/jquery-2.1.4.min.js"></script>
|
|
|
<script>
|
|
|
if (typeof jQuery == 'undefined') {
|
|
|
document.write(unescape("%3Cscript src='jquery.js'%3E%3C/script%3E"));
|
|
|
}
|
|
|
</script>
|
|
|
</head>
|
|
|
<body class="light">
|
|
|
<!-- Set the theme before any content is loaded, prevents flash -->
|
|
|
<script type="text/javascript">
|
|
|
var theme = localStorage.getItem('theme');
|
|
|
if (theme == null) { theme = 'light'; }
|
|
|
$('body').removeClass().addClass(theme);
|
|
|
</script>
|
|
|
|
|
|
<!-- Hide / unhide sidebar before it is displayed -->
|
|
|
<script type="text/javascript">
|
|
|
var sidebar = localStorage.getItem('sidebar');
|
|
|
if (sidebar === "hidden") { $("html").addClass("sidebar-hidden") }
|
|
|
else if (sidebar === "visible") { $("html").addClass("sidebar-visible") }
|
|
|
</script>
|
|
|
|
|
|
<div id="sidebar" class="sidebar">
|
|
|
<ul class="chapter"><li><a href="ch01-00-introduction.html"><strong>1.</strong> 介绍</a></li><li><ul class="section"><li><a href="ch01-01-installation.html"><strong>1.1.</strong> 安装</a></li><li><a href="ch01-02-hello-world.html"><strong>1.2.</strong> Hello, World!</a></li></ul></li><li><a href="ch02-00-guessing-game-tutorial.html"><strong>2.</strong> 猜猜看教程</a></li><li><a href="ch03-00-common-programming-concepts.html"><strong>3.</strong> 通用编程概念</a></li><li><ul class="section"><li><a href="ch03-01-variables-and-mutability.html"><strong>3.1.</strong> 变量和可变性</a></li><li><a href="ch03-02-data-types.html"><strong>3.2.</strong> 数据类型</a></li><li><a href="ch03-03-how-functions-work.html"><strong>3.3.</strong> 函数如何工作</a></li><li><a href="ch03-04-comments.html" class="active"><strong>3.4.</strong> 注释</a></li><li><a href="ch03-05-control-flow.html"><strong>3.5.</strong> 控制流</a></li></ul></li><li><a href="ch04-00-understanding-ownership.html"><strong>4.</strong> 认识所有权</a></li><li><ul class="section"><li><a href="ch04-01-what-is-ownership.html"><strong>4.1.</strong> 什么是所有权</a></li><li><a href="ch04-02-references-and-borrowing.html"><strong>4.2.</strong> 引用 & 借用</a></li><li><a href="ch04-03-slices.html"><strong>4.3.</strong> Slices</a></li></ul></li><li><a href="ch05-00-structs.html"><strong>5.</strong> 结构体</a></li><li><ul class="section"><li><a href="ch05-01-method-syntax.html"><strong>5.1.</strong> 方法语法</a></li></ul></li><li><a href="ch06-00-enums.html"><strong>6.</strong> 枚举和模式匹配</a></li><li><ul class="section"><li><a href="ch06-01-defining-an-enum.html"><strong>6.1.</strong> 定义枚举</a></li><li><a href="ch06-02-match.html"><strong>6.2.</strong> <code>match</code>控制流运算符</a></li><li><a href="ch06-03-if-let.html"><strong>6.3.</strong> <code>if let</code>简单控制流</a></li></ul></li><li><a href="ch07-00-modules.html"><strong>7.</strong> 模块</a></li><li><ul class="section"><li><a href="ch07-01-mod-and-the-filesystem.html"><strong>7.1.</strong> <code>mod</code>和文件系统</a></li><li><a href="ch07-02-controlling-visibility-with-pub.html"><strong>7.2.</strong> 使用<code>pub</code>控制可见性</a></li><li><a href="ch07-03-importing-names-with-use.html"><strong>7.3.</strong> 使用<code>use</code>导入命名</a></li></ul></li><li><a href="ch08-00-common-collections.html"><strong>8.</strong> 通用集合类型</a></li><li><ul class="section"><li><a href="ch08-01-vectors.html"><strong>8.1.</strong> vector</a></li><li><a href="ch08-02-strings.html"><strong>8.2.</strong> 字符串</a></li><li><a href="ch08-03-hash-maps.html"><strong>8.3.</strong> 哈希 map</a></li></ul></li><li><a href="ch09-00-error-handling.html"><strong>9.</strong> 错误处理</a></li><li><ul class="section"><li><a href="ch09-01-unrecoverable-errors-with-panic.html"><strong>9.1.</strong> <code>panic!</code>与不可恢复的错误</a></li><li><a href="ch09-02-recoverable-errors-with-result.html"><strong>9.2.</strong> <code>Result</code>与可恢复的错误</a></li><li><a href="ch09-03-to-panic-or-not-to-panic.html"><strong>9.3.</strong> <code>panic!</code>还是不<code>panic!</code></a></li></ul></li><li><a href="ch10-00-generics.html"><strong>10.</strong> 泛型、trait 和生命周期</a></li><li><ul class="section"><li><a href="ch10-01-syntax.html"><strong>10.1.</strong> 泛型数据类型</a></li><li><a href="ch10-02-traits.html"><strong>10.2.</strong> trait：定义共享的行为</a></li><li><a href="ch10-03-lifetime-syntax.html"><strong>10.3.</strong> 生命周期与引用有效性</a></li></ul></li><li><a href="ch11-00-testing.html"><strong>11.</strong> 测试</a></li><li><ul class="section"><li><a href="ch11-01-writing-tests.html"><strong>11.1.</strong> 编写测试</a></li><li><a href="ch11-02-running-tests.html"><strong>11.2.</strong> 运行测试</a></li><li><a href="ch11-03-test-organization.html"><strong>11.3.</strong> 测试的组织结构</a></li></ul></li><li><a href="ch12-00-an-io-project.html"><strong>12.</strong> 一个 I/O 项目</a></li><li><ul class="section"><li><a href="ch12-01-accepting-command-line-arguments.html"><strong>12.1.</strong> 接受命令行参数</a></li><li><a href="ch12-02-reading-a-file.html"><strong>12.2.</strong> 读取文件</a></li><li><a href="ch12-03-improving-error-handling-and-modularity.html"><strong>12.3.</strong> 增强错误处理和模块化</a></li><li><a href="ch12-04-testing-the-librarys-functionality.html"><strong>12.4.</strong> 测试库的功能</a></li><li><a href="ch12-05-working-with-environment-variables.html"><strong>12.5.</strong> 处理环境变量</a></li><li><a href="ch12-06-writing-to-stderr-instead-of-stdout.html"><strong>12.6.</strong> 输出到<code>stderr</code>而不是<code>stdout</code></a></li></ul></li><li><a href="ch13-00-functional-features.html"><strong>13.</strong> Rust 中的函数式语言功能</a></li><li><ul class="section"><li><a href="ch13-01-closures.html"><strong>13.1.</strong> 闭包</a></li><li><a href="ch13-02-iterators.html"><strong>13.2.</strong> 迭代器</a></li><li><a href="ch13-03-improving-our-io-project.html"><strong>13.3.</strong> 改进 I/O 项目</a></li><li><a href="ch13-04-performance.html"><strong>13.4.</strong> 性能</a></li></ul></li><li><a href="ch14-00-more-about-cargo.html"><strong>14.</strong> 更多关于 Cargo 和 Crates.io</a></li><li><ul class="section"><li><a href="ch14-01-release-profiles.html"><strong>14.1.</strong> 发布配置</a></li><li><a href="ch14-02-publishing-to-crates-io.html"><strong>14.2.</strong> 将 crate 发布到 Crates.io</a></li><li><a href="ch14-03-cargo-workspaces.html"><strong>14.3.</strong> Cargo 工作空间</a></li><li><a href="ch14-04-installing-binaries.html"><strong>14.4.</strong> 使用<code>cargo install</code>从 Crates.io 安装文件</a></li><li><a href="ch14-05-extending-cargo.html"><strong>14.5.</strong> Cargo 自定义扩展命令</a></li></ul></li><li><a href="ch15-00-smart-pointers.html"><strong>15.</strong> 智能指针</a></li><li><ul class="section"><li><a href="ch15-01-box.html"><strong>15.1.</strong> <code>Box<T></code>用于已知大小的堆上数据</a></li><li><a href="ch15-02-deref.html"><strong>15.2.</strong> <code>Deref</code> Trait 允许通过引用访问数据</a></li><li><a href="ch15-03-drop.html"><strong>15.3.</strong> <code>Drop</code> Trait 运行清理代码</a></li><li><a href="ch15-04-rc.html"><strong>15.4.</strong> <code>Rc<T></code> 引用计数智能指针</a></li><li><a href="ch15-05-interior-mutability.html"><strong>15.5.</strong> <code>RefCell<T></code>和内部可变性模式</a></li><li><a href="ch15-06-reference-cycles.html"><strong>15.6.</strong> 引用循环和内存泄漏是安全的</a></li></ul></li><li><a href="ch16-00-concurrency.html"><strong>16.</strong> 无畏并发</a></li><li><ul class="section"><li><a href="ch16-01-threads.html"><strong>16.1.</strong> 线程</a></li><li><a href="ch16-02-message-passing.html"><strong>16.2.</strong> 消息传递</a></li><li><a href="ch16-03-shared-state.html"><strong>16.3.</strong> 共享状态</a></li><li><a href="ch16-04-extensible-concurrency-sync-and-send.html"><strong>16.4.</strong> 可扩展的并发：<code>Sync</code>和<code>Send</code></a></li></ul></li><li><a href="ch17-00-oop.html"><strong>17.</strong> 面向对象</a></li><li><ul class="section"><li><a href="ch17-01-what-is-oo.html"><strong>17.1.</strong> 什么是面向对象</a></li><li><a href="ch17-02-trait-objects.html"><strong>17.2.</strong> trait对象</a></li></ul></li></ul>
|
|
|
</div>
|
|
|
|
|
|
<div id="page-wrapper" class="page-wrapper">
|
|
|
|
|
|
<div class="page">
|
|
|
<div id="menu-bar" class="menu-bar">
|
|
|
<div class="left-buttons">
|
|
|
<i id="sidebar-toggle" class="fa fa-bars"></i>
|
|
|
<i id="theme-toggle" class="fa fa-paint-brush"></i>
|
|
|
</div>
|
|
|
|
|
|
<h1 class="menu-title">Rust 程序设计语言 简体中文版</h1>
|
|
|
|
|
|
<div class="right-buttons">
|
|
|
<i id="print-button" class="fa fa-print" title="Print this book"></i>
|
|
|
</div>
|
|
|
</div>
|
|
|
|
|
|
<div id="content" class="content">
|
|
|
<a class="header" href="#注释" name="注释"><h2>注释</h2></a>
|
|
|
<blockquote>
|
|
|
<p><a href="https://github.com/rust-lang/book/blob/master/second-edition/src/ch03-04-comments.md">ch03-04-comments.md</a>
|
|
|
<br>
|
|
|
commit 4f2dc564851dc04b271a2260c834643dfd86c724</p>
|
|
|
</blockquote>
|
|
|
<p>所有编程语言都力求使他们的代码易于理解，不过有时需要提供额外的解释。在这种情况下，程序员在源码中留下记录，或者<strong>注释</strong>（<em>comments</em>），编译器会忽略他们不过其他阅读代码的人可能会用得上。</p>
|
|
|
<p>这是一个注释的例子：</p>
|
|
|
<pre><code class="language-rust">// Hello, world.
|
|
|
</code></pre>
|
|
|
<p>在 Rust 中，注释必须以两道斜杠开始并持续到本行的结尾。对于超过一行的注释，需要在每一行都加上<code>//</code>，像这样：</p>
|
|
|
<pre><code class="language-rust">// So we’re doing something complicated here, long enough that we need
|
|
|
// multiple lines of comments to do it! Whew! Hopefully, this comment will
|
|
|
// explain what’s going on.
|
|
|
</code></pre>
|
|
|
<p>注释也可以在放在包含代码的行的末尾：</p>
|
|
|
<p><span class="filename">Filename: src/main.rs</span></p>
|
|
|
<pre><code class="language-rust">fn main() {
|
|
|
let lucky_number = 7; // I’m feeling lucky today.
|
|
|
}
|
|
|
</code></pre>
|
|
|
<p>不过你会经常看到他们被以这种格式使用，也就是位于它所解释的代码行的上面一行：</p>
|
|
|
<p><span class="filename">Filename: src/main.rs</span></p>
|
|
|
<pre><code class="language-rust">fn main() {
|
|
|
// I’m feeling lucky today.
|
|
|
let lucky_number = 7;
|
|
|
}
|
|
|
</code></pre>
|
|
|
<p>这就是注释的全部。并没有什么特别复杂的。</p>
|
|
|
|
|
|
</div>
|
|
|
|
|
|
<!-- Mobile navigation buttons -->
|
|
|
|
|
|
<a href="ch03-03-how-functions-work.html" class="mobile-nav-chapters previous">
|
|
|
<i class="fa fa-angle-left"></i>
|
|
|
</a>
|
|
|
|
|
|
|
|
|
|
|
|
<a href="ch03-05-control-flow.html" class="mobile-nav-chapters next">
|
|
|
<i class="fa fa-angle-right"></i>
|
|
|
</a>
|
|
|
|
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
<a href="ch03-03-how-functions-work.html" class="nav-chapters previous" title="You can navigate through the chapters using the arrow keys">
|
|
|
<i class="fa fa-angle-left"></i>
|
|
|
</a>
|
|
|
|
|
|
|
|
|
|
|
|
<a href="ch03-05-control-flow.html" class="nav-chapters next" title="You can navigate through the chapters using the arrow keys">
|
|
|
<i class="fa fa-angle-right"></i>
|
|
|
</a>
|
|
|
|
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
<!-- Local fallback for Font Awesome -->
|
|
|
<script>
|
|
|
if ($(".fa").css("font-family") !== "FontAwesome") {
|
|
|
$('<link rel="stylesheet" type="text/css" href="_FontAwesome/css/font-awesome.css">').prependTo('head');
|
|
|
}
|
|
|
</script>
|
|
|
|
|
|
<!-- Livereload script (if served using the cli tool) -->
|
|
|
|
|
|
|
|
|
<script src="highlight.js"></script>
|
|
|
<script src="book.js"></script>
|
|
|
</body>
|
|
|
</html>
|
