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<main>
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<h1 id="rust-中的函数式语言功能迭代器与闭包"><a class="header" href="#rust-中的函数式语言功能迭代器与闭包">Rust 中的函数式语言功能：迭代器与闭包</a></h1>
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<blockquote>
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<p><a href="https://github.com/rust-lang/book/blob/main/src/ch13-00-functional-features.md">ch13-00-functional-features.md</a>
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<br>
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commit daa268a0cd04ef76a8067a26ed7d28ec2a9336d3</p>
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</blockquote>
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<p>Rust 的设计灵感来源于很多现存的语言和技术。其中一个显著的影响就是 <strong>函数式编程</strong>（<em>functional programming</em>）。函数式编程风格通常包含将函数作为参数值或其他函数的返回值、将函数赋值给变量以供之后执行等等。</p>
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<p>本章我们不会讨论函数式编程是或不是什么的问题，而是展示 Rust 的一些在功能上与其他被认为是函数式语言类似的特性。</p>
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<p>更具体的，我们将要涉及：</p>
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<ul>
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<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>
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<li><strong>迭代器</strong>（<em>Iterators</em>），一种处理元素序列的方式</li>
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<li>如何使用闭包和迭代器来改进第十二章的 I/O 项目。</li>
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<li>闭包和迭代器的性能。（<strong>剧透警告：</strong> 它们的速度超乎你的想象！）</li>
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</ul>
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<p>我们已经介绍了其它受函数式风格影响的 Rust 功能，比如模式匹配和枚举，这些已经在其他章节中讲到过了。因为掌握闭包和迭代器是编写符合语言风格的高性能 Rust 代码的重要一环，所以我们将专门用一整章来讲解它们。</p>
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