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<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" class="active"><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&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><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><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> 为使用不同类型的值而设计的 trait 对象</a></li><li><a href="ch17-03-oo-design-patterns.html"><strong>17.3.</strong> 面向对象设计模式的实现</a></li></ul></li><li><a href="ch18-00-patterns.html"><strong>18.</strong> 模式用来匹配值的结构</a></li><li><ul class="section"><li><a href="ch18-01-all-the-places-for-patterns.html"><strong>18.1.</strong> 所有可能会用到模式的位置</a></li><li><a href="ch18-02-refutability.html"><strong>18.2.</strong> refutable何时模式可能会匹配失败</a></li><li><a href="ch18-03-pattern-syntax.html"><strong>18.3.</strong> 模式的全部语法</a></li></ul></li></ul>
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<h1 class="menu-title">Rust 程序设计语言 简体中文版</h1>
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<a class="header" href="#通用集合类型" name="通用集合类型"><h1>通用集合类型</h1></a>
<blockquote>
<p><a href="https://github.com/rust-lang/book/blob/master/second-edition/src/ch08-00-common-collections.md">ch08-00-common-collections.md</a>
<br>
commit e6d6caab41471f7115a621029bd428a812c5260e</p>
</blockquote>
<p>Rust 标准库中包含一系列被称为<strong>集合</strong><em>collections</em>)的非常有用的数据结构。大部分其他数据类型都代表一个特定的值,不过集合可以包含多个值。不同于内建的数组和元组类型,这些集合指向的数据是储存在堆上的,这意味着数据的数量不必在编译时就可知并且可以随着程序的运行增长或缩小。每种集合都有着不同能力和代价,而为所处的场景选择合适的集合则是你将要始终发展的技能。在这一章里,我们将详细的了解三个在 Rust 程序中被广泛使用的集合:</p>
<ul>
<li><em>vector</em> 允许我们一个挨着一个地储存一系列数量可变的值</li>
<li><strong>字符串</strong><em>string</em>)是一个字符的集合。我们之前见过<code>String</code>类型,现在将详细介绍它。</li>
<li><strong>哈希 map</strong><em>hash map</em>允许我们将值与一个特定的键key相关联。这是一个叫做 <em>map</em> 的更通用的数据结构的特定实现。</li>
</ul>
<p>对于标准库提供的其他类型的集合,请查看<a href="https://doc.rust-lang.org/std/collections">文档</a></p>
<p>我们将讨论如何创建和更新 vector、字符串和哈希 map以及他们有什么不同。</p>
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