You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
trpl-zh-cn/docs/ch13-00-functional-features...

132 lines
12 KiB

This file contains ambiguous Unicode characters!

This file contains ambiguous Unicode characters that may be confused with others in your current locale. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to highlight these characters.

<!DOCTYPE HTML>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Rust 中的函数式语言功能 - 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"><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 &amp; 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" class="active"><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&lt;T&gt;</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&lt;T&gt;</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&lt;T&gt;</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></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="#rust-中的函数式语言功能--迭代器和闭包" name="rust-中的函数式语言功能--迭代器和闭包"><h1>Rust 中的函数式语言功能 —— 迭代器和闭包</h1></a>
<blockquote>
<p><a href="https://github.com/rust-lang/book/blob/master/second-edition/src/ch13-00-functional-features.md">ch13-00-functional-features.md</a>
<br>
commit 4f2dc564851dc04b271a2260c834643dfd86c724</p>
</blockquote>
<p>Rust 的设计灵感来源于很多前人的成果。影响 Rust 的其中之一就是函数式编程,在这里函数也是值并可以被用作参数或其他函数的返回值、赋值给变量等等。我们将回避解释函数式编程的具体是什么以及其优缺点,而是突出展示 Rust 中那些类似被认为是函数式的编程语言中的功能。</p>
<p>更具体的,我们将要涉及:</p>
<ul>
<li><strong>闭包</strong><em>Closures</em>),一个可以储存在变量里的类似函数的结构</li>
<li><strong>迭代器</strong><em>Iterators</em>),一种处理元素序列的方式。。</li>
<li>如何使用这些功能来改进上一章的项目</li>
<li>这些功能的性能。**剧透高能:**他们的速度超乎想象!</li>
</ul>
<p>这并不是一个 Rust 受函数式风格影响的完整功能列表:还有模式匹配、枚举和很多其他功能。不过掌握闭包和迭代器则是编写符合语言风格的快速的 Rust 代码的重要一环。</p>
</div>
<!-- Mobile navigation buttons -->
<a href="ch12-06-writing-to-stderr-instead-of-stdout.html" class="mobile-nav-chapters previous">
<i class="fa fa-angle-left"></i>
</a>
<a href="ch13-01-closures.html" class="mobile-nav-chapters next">
<i class="fa fa-angle-right"></i>
</a>
</div>
<a href="ch12-06-writing-to-stderr-instead-of-stdout.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="ch13-01-closures.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>