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<h1 id="高级特性"><a class="header" href="#高级特性">高级特性</a></h1>
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<blockquote>
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<p><a href="https://github.com/rust-lang/book/blob/main/src/ch20-00-advanced-features.md">ch20-00-advanced-features.md</a>
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<br>
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commit a8536189d5f1ba2f0b1187bfae787c0d89e2871c</p>
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</blockquote>
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<p>现在我们已经学习了 Rust 编程语言中最常用的部分。在第二十一章开始另一个新项目之前，让我们聊聊一些总有一天你会遇上的部分内容。你可以将本章作为不经意间遇到未知的内容时的参考。本章将要学习的功能在一些非常特定的场景下很有用处。虽然很少会碰到它们，我们希望确保你了解 Rust 提供的所有功能。</p>
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<p>本章将涉及如下内容：</p>
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<ul>
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<li>不安全 Rust：用于当需要舍弃 Rust 的某些保证并负责手动维持这些保证</li>
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<li>高级 trait：与 trait 相关的关联类型，默认类型参数，完全限定语法（fully qualified syntax），超（父）trait（supertraits）和 newtype 模式</li>
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<li>高级类型：关于 newtype 模式的更多内容，类型别名，never 类型和动态大小类型</li>
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<li>高级函数和闭包：函数指针和返回闭包</li>
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<li>宏：定义在编译时定义更多代码的方式</li>
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</ul>
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<p>对所有人而言，这都是一个介绍 Rust 迷人特性的宝典！让我们翻开它吧！</p>
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