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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" 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>导入命名空间</a></li></ul></li></ul>
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<h1 class="menu-title">Rust 程序设计语言 中文版</h1>
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<h2>注释</h2>
<blockquote>
<p><a href="https://github.com/rust-lang/book/blob/master/src/ch03-04-comments.md">ch03-04-comments.md</a>
<br>
commit 74d6fc999b986b74bf94edd6dcbb5a08a16c12de</p>
</blockquote>
<p>所有编程语言都力求使他们的代码易于理解，不过有时额外的解释需要得到保障。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结尾：</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>
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