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<ol class="chapter"><li class="chapter-item affix "><a href="../about-book.html">关于本书</a></li><li class="chapter-item affix "><a href="../into-rust.html">进入 Rust 编程世界</a></li><li class="chapter-item affix "><a href="../first-try/sth-you-should-not-do.html">避免从入门到放弃</a></li><li class="chapter-item affix "><a href="../community.html">社区和锈书</a></li><li class="spacer"></li><li class="chapter-item affix "><a href="../some-thoughts.html">Datav: 可编程的数据可视化平台和可观测性平台</a></li><li class="chapter-item affix "><li class="part-title">Rust 语言基础学习</li><li class="spacer"></li><li class="chapter-item "><a href="../first-try/intro.html"><strong aria-hidden="true">1.</strong> 寻找牛刀，以便小试</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../first-try/installation.html"><strong aria-hidden="true">1.1.</strong> 安装 Rust 环境</a></li><li class="chapter-item "><a href="../first-try/editor.html"><strong aria-hidden="true">1.2.</strong> 墙推 VSCode!</a></li><li class="chapter-item "><a href="../first-try/cargo.html"><strong aria-hidden="true">1.3.</strong> 认识 Cargo</a></li><li class="chapter-item "><a href="../first-try/hello-world.html"><strong aria-hidden="true">1.4.</strong> 不仅仅是 Hello world</a></li><li class="chapter-item "><a href="../first-try/slowly-downloading.html"><strong aria-hidden="true">1.5.</strong> 下载依赖太慢了？</a></li></ol></li><li class="chapter-item expanded "><a href="../basic/intro.html"><strong aria-hidden="true">2.</strong> Rust 基础入门</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../basic/variable.html"><strong aria-hidden="true">2.1.</strong> 变量绑定与解构</a></li><li class="chapter-item "><a href="../basic/base-type/index.html"><strong aria-hidden="true">2.2.</strong> 基本类型</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../basic/base-type/numbers.html"><strong aria-hidden="true">2.2.1.</strong> 数值类型</a></li><li class="chapter-item "><a href="../basic/base-type/char-bool.html"><strong aria-hidden="true">2.2.2.</strong> 字符、布尔、单元类型</a></li><li class="chapter-item "><a href="../basic/base-type/statement-expression.html"><strong aria-hidden="true">2.2.3.</strong> 语句与表达式</a></li><li class="chapter-item "><a href="../basic/base-type/function.html"><strong aria-hidden="true">2.2.4.</strong> 函数</a></li></ol></li><li class="chapter-item "><a href="../basic/ownership/index.html"><strong aria-hidden="true">2.3.</strong> 所有权和借用</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../basic/ownership/ownership.html"><strong aria-hidden="true">2.3.1.</strong> 所有权</a></li><li class="chapter-item "><a href="../basic/ownership/borrowing.html"><strong aria-hidden="true">2.3.2.</strong> 引用与借用</a></li></ol></li><li class="chapter-item "><a href="../basic/compound-type/intro.html"><strong aria-hidden="true">2.4.</strong> 复合类型</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../basic/compound-type/string-slice.html"><strong aria-hidden="true">2.4.1.</strong> 字符串与切片</a></li><li class="chapter-item "><a href="../basic/compound-type/tuple.html"><strong aria-hidden="true">2.4.2.</strong> 元组</a></li><li class="chapter-item "><a href="../basic/compound-type/struct.html"><strong aria-hidden="true">2.4.3.</strong> 结构体</a></li><li class="chapter-item "><a href="../basic/compound-type/enum.html"><strong aria-hidden="true">2.4.4.</strong> 枚举</a></li><li class="chapter-item "><a href="../basic/compound-type/array.html"><strong aria-hidden="true">2.4.5.</strong> 数组</a></li></ol></li><li class="chapter-item "><a href="../basic/flow-control.html"><strong aria-hidden="true">2.5.</strong> 流程控制</a></li><li class="chapter-item "><a href="../basic/match-pattern/intro.html"><strong aria-hidden="true">2.6.</strong> 模式匹配</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../basic/match-pattern/match-if-let.html"><strong aria-hidden="true">2.6.1.</strong> match 和 if let</a></li><li class="chapter-item "><a href="../basic/match-pattern/option.html"><strong aria-hidden="true">2.6.2.</strong> 解构 Option</a></li><li class="chapter-item "><a href="../basic/match-pattern/pattern-match.html"><strong aria-hidden="true">2.6.3.</strong> 模式适用场景</a></li><li class="chapter-item "><a href="../basic/match-pattern/all-patterns.html"><strong aria-hidden="true">2.6.4.</strong> 全模式列表</a></li></ol></li><li class="chapter-item "><a href="../basic/method.html"><strong aria-hidden="true">2.7.</strong> 方法 Method</a></li><li class="chapter-item "><a href="../basic/trait/intro.html"><strong aria-hidden="true">2.8.</strong> 泛型和特征</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../basic/trait/generic.html"><strong aria-hidden="true">2.8.1.</strong> 泛型 Generics</a></li><li class="chapter-item "><a href="../basic/trait/trait.html"><strong aria-hidden="true">2.8.2.</strong> 特征 Trait</a></li><li class="chapter-item "><a href="../basic/trait/trait-object.html"><strong aria-hidden="true">2.8.3.</strong> 特征对象</a></li><li class="chapter-item "><a href="../basic/trait/advance-trait.html"><strong aria-hidden="true">2.8.4.</strong> 进一步深入特征</a></li></ol></li><li class="chapter-item "><a href="../basic/collections/intro.html"><strong aria-hidden="true">2.9.</strong> 集合类型</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../basic/collections/vector.html"><strong aria-hidden="true">2.9.1.</strong> 动态数组 Vector</a></li><li class="chapter-item "><a href="../basic/collections/hashmap.html"><strong aria-hidden="true">2.9.2.</strong> KV 存储 HashMap</a></li></ol></li><li class="chapter-item "><a href="../basic/lifetime.html"><strong aria-hidden="true">2.10.</strong> 认识生命周期</a></li><li class="chapter-item "><a href="../basic/result-error/intro.html"><strong aria-hidden="true">2.11.</strong> 返回值和错误处理</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../basic/result-error/panic.html"><strong aria-hidden="true">2.11.1.</strong> panic! 深入剖析</a></li><li class="chapter-item "><a href="../basic/result-error/result.html"><strong aria-hidden="true">2.11.2.</strong> 返回值 Result 和?</a></li></ol></li><li class="chapter-item "><a href="../basic/crate-module/intro.html"><strong aria-hidden="true">2.12.</strong> 包和模块</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../basic/crate-module/crate.html"><strong aria-hidden="true">2.12.1.</strong> 包 Crate</a></li><li class="chapter-item "><a href="../basic/crate-module/module.html"><strong aria-hidden="true">2.12.2.</strong> 模块 Module</a></li><li class="chapter-item "><a href="../basic/crate-module/use.html"><strong aria-hidden="true">2.12.3.</strong> 使用 use 引入模块及受限可见性</a></li></ol></li><li class="chapter-item "><a href="../basic/comment.html"><strong aria-hidden="true">2.13.</strong> 注释和文档</a></li><li class="chapter-item expanded "><a href="../basic/formatted-output.html" class="active"><strong aria-hidden="true">2.14.</strong> 格式化输出</a></li></ol></li><li class="chapter-item "><a href="../basic-practice/intro.html"><strong aria-hidden="true">3.</strong> 入门实战：文件搜索工具</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../basic-practice/base-features.html"><strong aria-hidden="true">3.1.</strong> 基本功能</a></li><li class="chapter-item "><a href="../basic-practice/refactoring.html"><strong aria-hidden="true">3.2.</strong> 增加模块化和错误处理</a></li><li class="chapter-item "><a href="../basic-practice/tests.html"><strong aria-hidden="true">3.3.</strong> 测试驱动开发</a></li><li class="chapter-item "><a href="../basic-practice/envs.html"><strong aria-hidden="true">3.4.</strong> 使用环境变量</a></li><li class="chapter-item "><a href="../basic-practice/stderr.html"><strong aria-hidden="true">3.5.</strong> 重定向错误信息的输出</a></li><li class="chapter-item "><a href="../basic-practice/iterators.html"><strong aria-hidden="true">3.6.</strong> 使用迭代器来改进程序(可选)</a></li></ol></li><li class="chapter-item "><li class="part-title">Rust 语言进阶学习</li><li class="spacer"></li><li class="chapter-item "><a href="../advance/intro.html"><strong aria-hidden="true">4.</strong> Rust 高级进阶</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../advance/lifetime/intro.html"><strong aria-hidden="true">4.1.</strong> 生命周期</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../advance/lifetime/advance.html"><strong aria-hidden="true">4.1.1.</strong> 深入生命周期</a></li><li class="chapter-item "><a href="../advance/lifetime/static.html"><strong aria-hidden="true">4.1.2.</strong> &'static 和 T: 'static</a></li></ol></li><li class="chapter-item "><a href="../advance/functional-programing/intro.html"><strong aria-hidden="true">4.2.</strong> 函数式编程: 闭包、迭代器</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../advance/functional-programing/closure.html"><strong aria-hidden="true">4.2.1.</strong> 闭包 Closure</a></li><li class="chapter-item "><a href="../advance/functional-programing/iterator.html"><strong aria-hidden="true">4.2.2.</strong> 迭代器 Iterator</a></li></ol></li><li class="chapter-item "><a href="../advance/into-types/intro.html"><strong aria-hidden="true">4.3.</strong> 深入类型</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../advance/into-types/converse.html"><strong aria-hidden="true">4.3.1.</strong> 类型转换</a></li><li class="chapter-item "><a href="../advance/into-types/custom-type.html"><strong aria-hidden="true">4.3.2.</strong> newtype 和 类型别名</a></li><li class="chapter-item "><a href="../advance/into-types/sized.html"><strong aria-hidden="true">4.3.3.</strong> Sized 和不定长类型 DST</a></li><li class="chapter-item "><a href="../advance/into-types/enum-int.html"><strong aria-hidden="true">4.3.4.</strong> 枚举和整数</a></li></ol></li><li class="chapter-item "><a href="../advance/smart-pointer/intro.html"><strong aria-hidden="true">4.4.</strong> 智能指针</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../advance/smart-pointer/box.html"><strong aria-hidden="true">4.4.1.</strong> Box堆对象分配</a></li><li class="chapter-item "><a href="../advance/smart-pointer/deref.html"><strong aria-hidden="true">4.4.2.</strong> Deref 解引用</a></li><li class="chapter-item "><a href="../advance/smart-pointer/drop.html"><strong aria-hidden="true">4.4.3.</strong> Drop 释放资源</a></li><li class="chapter-item "><a href="../advance/smart-pointer/rc-arc.html"><strong aria-hidden="true">4.4.4.</strong> Rc 与 Arc 实现 1vN 所有权机制</a></li><li class="chapter-item "><a href="../advance/smart-pointer/cell-refcell.html"><strong aria-hidden="true">4.4.5.</strong> Cell 与 RefCell 内部可变性</a></li></ol></li><li class="chapter-item "><a href="../advance/circle-self-ref/intro.html"><strong aria-hidden="true">4.5.</strong> 循环引用与自引用</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../advance/circle-self-ref/circle-reference.html"><strong aria-hidden="true">4.5.1.</strong> Weak 与循环引用</a></li><li class="chapter-item "><a href="../advance/circle-self-ref/self-referential.html"><strong aria-hidden="true">4.5.2.</strong> 结构体中的自引用</a></li></ol></li><li class="chapter-item "><a href="../advance/concurrency-with-threads/intro.html"><strong aria-hidden="true">4.6.</strong> 多线程并发编程</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../advance/concurrency-with-threads/concurrency-parallelism.html"><strong aria-hidden="true">4.6.1.</strong> 并发和并行</a></li><li class="chapter-item "><a href="../advance/concurrency-with-threads/thread.html"><strong aria-hidden="true">4.6.2.</strong> 使用多线程</a></li><li class="chapter-item "><a href="../advance/concurrency-with-threads/message-passing.html"><strong aria-hidden="true">4.6.3.</strong> 线程同步：消息传递</a></li><li class="chapter-item "><a href="../advance/concurrency-with-threads/sync1.html"><strong aria-hidden="true">4.6.4.</strong> 线程同步：锁、Condvar 和信号量</a></li><li class="chapter-item "><a href="../advance/concurrency-with-threads/sync2.html"><strong aria-hidden="true">4.6.5.</strong> 线程同步：Atomic 原子操作与内存顺序</a></li><li class="chapter-item "><a href="../advance/concurrency-with-threads/send-sync.html"><strong aria-hidden="true">4.6.6.</strong> 基于 Send 和 Sync 的线程安全</a></li></ol></li><li class="chapter-item "><a href="../advance/global-variable.html"><strong aria-hidden="true">4.7.</strong> 全局变量</a></li><li class="chapter-item "><a href="../advance/errors.html"><strong aria-hidden="true">4.8.</strong> 错误处理</a></li><li class="chapter-item "><a href="../advance/unsafe/intro.html"><strong aria-hidden="true">4.9.</strong> Unsafe Rust</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../advance/unsafe/superpowers.html"><strong aria-hidden="true">4.9.1.</strong> 五种兵器</a></li><li class="chapter-item "><a href="../advance/unsafe/inline-asm.html"><strong aria-hidden="true">4.9.2.</strong> 内联汇编</a></li></ol></li><li class="chapter-item "><a href="../advance/macro.html"><strong aria-hidden="true">4.10.</strong> Macro 宏编程</a></li><li class="chapter-item "><a href="../advance/async/intro.html"><strong aria-hidden="true">4.11.</strong> async/await 异步编程</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../advance/async/getting-started.html"><strong aria-hidden="true">4.11.1.</strong> async 编程入门</a></li><li class="chapter-item "><a href="../advance/async/future-excuting.html"><strong aria-hidden="true">4.11.2.</strong> 底层探秘: Future 执行与任务调度</a></li><li class="chapter-item "><a href="../advance/async/pin-unpin.html"><strong aria-hidden="true">4.11.3.</strong> 定海神针 Pin 和 Unpin</a></li><li class="chapter-item "><a href="../advance/async/async-await.html"><strong aria-hidden="true">4.11.4.</strong> async/await 和 Stream 流处理</a></li><li class="chapter-item "><a href="../advance/async/multi-futures-simultaneous.html"><strong aria-hidden="true">4.11.5.</strong> 同时运行多个 Future</a></li><li class="chapter-item "><a href="../advance/async/pain-points-and-workarounds.html"><strong aria-hidden="true">4.11.6.</strong> 一些疑难问题的解决办法</a></li><li class="chapter-item "><a href="../advance/async/web-server.html"><strong aria-hidden="true">4.11.7.</strong> 实践应用：Async Web 服务器</a></li></ol></li></ol></li><li class="chapter-item "><a href="../advance-practice1/intro.html"><strong aria-hidden="true">5.</strong> 进阶实战1: 实现一个 web 服务器</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../advance-practice1/web-server.html"><strong aria-hidden="true">5.1.</strong> 单线程版本</a></li><li class="chapter-item "><a href="../advance-practice1/multi-threads.html"><strong aria-hidden="true">5.2.</strong> 多线程版本</a></li><li class="chapter-item "><a href="../advance-practice1/graceful-shutdown.html"><strong aria-hidden="true">5.3.</strong> 优雅关闭和资源清理</a></li></ol></li><li class="chapter-item "><a href="../advance-practice/intro.html"><strong aria-hidden="true">6.</strong> 进阶实战2: 实现一个简单 Redis</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../advance-practice/overview.html"><strong aria-hidden="true">6.1.</strong> tokio 概览</a></li><li class="chapter-item "><a href="../advance-practice/getting-startted.html"><strong aria-hidden="true">6.2.</strong> 使用初印象</a></li><li class="chapter-item "><a href="../advance-practice/spawning.html"><strong aria-hidden="true">6.3.</strong> 创建异步任务</a></li><li class="chapter-item "><a href="../advance-practice/shared-state.html"><strong aria-hidden="true">6.4.</strong> 共享状态</a></li><li class="chapter-item "><a href="../advance-practice/channels.html"><strong aria-hidden="true">6.5.</strong> 消息传递</a></li><li class="chapter-item "><a href="../advance-practice/io.html"><strong aria-hidden="true">6.6.</strong> I/O</a></li><li class="chapter-item "><a href="../advance-practice/frame.html"><strong aria-hidden="true">6.7.</strong> 解析数据帧</a></li><li class="chapter-item "><a href="../advance-practice/async.html"><strong aria-hidden="true">6.8.</strong> 深入 async</a></li><li class="chapter-item "><a href="../advance-practice/select.html"><strong aria-hidden="true">6.9.</strong> select</a></li><li class="chapter-item "><a href="../advance-practice/stream.html"><strong aria-hidden="true">6.10.</strong> 类似迭代器的 Stream</a></li><li class="chapter-item "><a href="../advance-practice/graceful-shutdown.html"><strong aria-hidden="true">6.11.</strong> 优雅的关闭</a></li><li class="chapter-item "><a href="../advance-practice/bridging-with-sync.html"><strong aria-hidden="true">6.12.</strong> 异步跟同步共存</a></li></ol></li><li class="chapter-item "><a href="../difficulties/intro.html"><strong aria-hidden="true">7.</strong> Rust 难点攻关</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../difficulties/slice.html"><strong aria-hidden="true">7.1.</strong> 切片和切片引用</a></li><li class="chapter-item "><a href="../difficulties/eq.html"><strong aria-hidden="true">7.2.</strong> Eq 和 PartialEq</a></li><li class="chapter-item "><a href="../difficulties/string.html"><strong aria-hidden="true">7.3.</strong> String、&str 和 str TODO</a></li><li class="chapter-item "><a href="../difficulties/lifetime.html"><strong aria-hidden="true">7.4.</strong> 作用域、生命周期和 NLL TODO</a></li><li class="chapter-item "><a href="../difficulties/move-copy.html"><strong aria-hidden="true">7.5.</strong> move、Copy 和 Clone TODO</a></li><li class="chapter-item "><a href="../advance/difficulties/pointer.html"><strong aria-hidden="true">7.6.</strong> 裸指针、引用和智能指针 TODO</a></li></ol></li><li class="chapter-item "><li class="part-title">常用工具链</li><li class="spacer"></li><li class="chapter-item "><a href="../test/intro.html"><strong aria-hidden="true">8.</strong> 自动化测试</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../test/write-tests.html"><strong aria-hidden="true">8.1.</strong> 编写测试及控制执行</a></li><li class="chapter-item "><a href="../test/unit-integration-test.html"><strong aria-hidden="true">8.2.</strong> 单元测试和集成测试</a></li><li class="chapter-item "><a href="../test/assertion.html"><strong aria-hidden="true">8.3.</strong> 断言 assertion</a></li><li class="chapter-item "><a href="../test/ci.html"><strong aria-hidden="true">8.4.</strong> 用 GitHub Actions 进行持续集成</a></li><li class="chapter-item "><a href="../test/benchmark.html"><strong aria-hidden="true">8.5.</strong> 基准测试 benchmark</a></li></ol></li><li class="chapter-item "><a href="../cargo/intro.html"><strong aria-hidden="true">9.</strong> Cargo 使用指南</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../cargo/getting-started.html"><strong aria-hidden="true">9.1.</strong> 上手使用</a></li><li class="chapter-item "><a href="../cargo/guide/intro.html"><strong aria-hidden="true">9.2.</strong> 基础指南</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../cargo/guide/why-exist.html"><strong aria-hidden="true">9.2.1.</strong> 为何会有 Cargo</a></li><li class="chapter-item "><a href="../cargo/guide/download-package.html"><strong aria-hidden="true">9.2.2.</strong> 下载并构建 Package</a></li><li class="chapter-item "><a href="../cargo/guide/dependencies.html"><strong aria-hidden="true">9.2.3.</strong> 添加依赖</a></li><li class="chapter-item "><a href="../cargo/guide/package-layout.html"><strong aria-hidden="true">9.2.4.</strong> Package 目录结构</a></li><li class="chapter-item "><a href="../cargo/guide/cargo-toml-lock.html"><strong aria-hidden="true">9.2.5.</strong> Cargo.toml vs Cargo.lock</a></li><li class="chapter-item "><a href="../cargo/guide/tests-ci.html"><strong aria-hidden="true">9.2.6.</strong> 测试和 CI</a></li><li class="chapter-item "><a href="../cargo/guide/cargo-cache.html"><strong aria-hidden="true">9.2.7.</strong> Cargo 缓存</a></li><li class="chapter-item "><a href="../cargo/guide/build-cache.html"><strong aria-hidden="true">9.2.8.</strong> Build 缓存</a></li></ol></li><li class="chapter-item "><a href="../cargo/reference/intro.html"><strong aria-hidden="true">9.3.</strong> 进阶指南</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../cargo/reference/specify-deps.html"><strong aria-hidden="true">9.3.1.</strong> 指定依赖项</a></li><li class="chapter-item "><a href="../cargo/reference/deps-overriding.html"><strong aria-hidden="true">9.3.2.</strong> 依赖覆盖</a></li><li class="chapter-item "><a href="../cargo/reference/manifest.html"><strong aria-hidden="true">9.3.3.</strong> Cargo.toml 清单详解</a></li><li class="chapter-item "><a href="../cargo/reference/cargo-target.html"><strong aria-hidden="true">9.3.4.</strong> Cargo Target</a></li><li class="chapter-item "><a href="../cargo/reference/workspaces.html"><strong aria-hidden="true">9.3.5.</strong> 工作空间 Workspace</a></li><li class="chapter-item "><a href="../cargo/reference/features/intro.html"><strong aria-hidden="true">9.3.6.</strong> 条件编译 Features</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../cargo/reference/features/examples.html"><strong aria-hidden="true">9.3.6.1.</strong> Features 示例</a></li></ol></li><li class="chapter-item "><a href="../cargo/reference/profiles.html"><strong aria-hidden="true">9.3.7.</strong> 发布配置 Profile</a></li><li class="chapter-item "><a href="../cargo/reference/configuration.html"><strong aria-hidden="true">9.3.8.</strong> 通过 config.toml 对 Cargo 进行配置</a></li><li class="chapter-item "><a href="../cargo/reference/publishing-on-crates.io.html"><strong aria-hidden="true">9.3.9.</strong> 发布到 crates.io</a></li><li class="chapter-item "><a href="../cargo/reference/build-script/intro.html"><strong aria-hidden="true">9.3.10.</strong> 构建脚本 build.rs</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../cargo/reference/build-script/examples.html"><strong aria-hidden="true">9.3.10.1.</strong> 构建脚本示例</a></li></ol></li></ol></li></ol></li><li class="chapter-item "><li class="part-title">开发实践</li><li class="spacer"></li><li class="chapter-item "><a href="../usecases/intro.html"><strong aria-hidden="true">10.</strong> 企业落地实践</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../usecases/aws-rust.html"><strong aria-hidden="true">10.1.</strong> AWS 为何这么喜欢 Rust?</a></li></ol></li><li class="chapter-item "><a href="../logs/intro.html"><strong aria-hidden="true">11.</strong> 日志和监控</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../logs/about-log.html"><strong aria-hidden="true">11.1.</strong> 日志详解</a></li><li class="chapter-item "><a href="../logs/log.html"><strong aria-hidden="true">11.2.</strong> 日志门面 log</a></li><li class="chapter-item "><a href="../logs/tracing.html"><strong aria-hidden="true">11.3.</strong> 使用 tracing 记录日志</a></li><li class="chapter-item "><a href="../logs/tracing-logger.html"><strong aria-hidden="true">11.4.</strong> 自定义 tracing 的输出格式</a></li><li class="chapter-item "><a href="../logs/observe/intro.html"><strong aria-hidden="true">11.5.</strong> 监控</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../logs/observe/about-observe.html"><strong aria-hidden="true">11.5.1.</strong> 可观测性</a></li><li class="chapter-item "><a href="../logs/observe/trace.html"><strong aria-hidden="true">11.5.2.</strong> 分布式追踪</a></li></ol></li></ol></li><li class="chapter-item "><a href="../practice/intro.html"><strong aria-hidden="true">12.</strong> Rust 最佳实践</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../practice/third-party-libs.html"><strong aria-hidden="true">12.1.</strong> 日常开发三方库精选</a></li><li class="chapter-item "><a href="../practice/naming.html"><strong aria-hidden="true">12.2.</strong> 命名规范</a></li><li class="chapter-item "><a href="../practice/interview.html"><strong aria-hidden="true">12.3.</strong> 面试经验</a></li><li class="chapter-item "><a href="../practice/best-pratice.html"><strong aria-hidden="true">12.4.</strong> 代码开发实践 todo</a></li></ol></li><li class="chapter-item "><a href="../too-many-lists/intro.html"><strong aria-hidden="true">13.</strong> 手把手带你实现链表</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../too-many-lists/do-we-need-it.html"><strong aria-hidden="true">13.1.</strong> 我们到底需不需要链表</a></li><li class="chapter-item "><a href="../too-many-lists/bad-stack/intro.html"><strong aria-hidden="true">13.2.</strong> 不太优秀的单向链表：栈</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../too-many-lists/bad-stack/layout.html"><strong aria-hidden="true">13.2.1.</strong> 数据布局</a></li><li class="chapter-item "><a href="../too-many-lists/bad-stack/basic-operations.html"><strong aria-hidden="true">13.2.2.</strong> 基本操作</a></li><li class="chapter-item "><a href="../too-many-lists/bad-stack/final-code.html"><strong aria-hidden="true">13.2.3.</strong> 最后实现</a></li></ol></li><li class="chapter-item "><a href="../too-many-lists/ok-stack/intro.html"><strong aria-hidden="true">13.3.</strong> 还可以的单向链表</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../too-many-lists/ok-stack/type-optimizing.html"><strong aria-hidden="true">13.3.1.</strong> 优化类型定义</a></li><li class="chapter-item "><a href="../too-many-lists/ok-stack/peek.html"><strong aria-hidden="true">13.3.2.</strong> 定义 Peek 函数</a></li><li class="chapter-item "><a href="../too-many-lists/ok-stack/iter.html"><strong aria-hidden="true">13.3.3.</strong> IntoIter 和 Iter</a></li><li class="chapter-item "><a href="../too-many-lists/ok-stack/itermut.html"><strong aria-hidden="true">13.3.4.</strong> IterMut 以及完整代码</a></li></ol></li><li class="chapter-item "><a href="../too-many-lists/persistent-stack/intro.html"><strong aria-hidden="true">13.4.</strong> 持久化单向链表</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../too-many-lists/persistent-stack/layout.html"><strong aria-hidden="true">13.4.1.</strong> 数据布局和基本操作</a></li><li class="chapter-item "><a href="../too-many-lists/persistent-stack/drop-arc.html"><strong aria-hidden="true">13.4.2.</strong> Drop、Arc 及完整代码</a></li></ol></li><li class="chapter-item "><a href="../too-many-lists/deque/intro.html"><strong aria-hidden="true">13.5.</strong> 不咋样的双端队列</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../too-many-lists/deque/layout.html"><strong aria-hidden="true">13.5.1.</strong> 数据布局和基本操作</a></li><li class="chapter-item "><a href="../too-many-lists/deque/peek.html"><strong aria-hidden="true">13.5.2.</strong> Peek</a></li><li class="chapter-item "><a href="../too-many-lists/deque/symmetric.html"><strong aria-hidden="true">13.5.3.</strong> 基本操作的对称镜像</a></li><li class="chapter-item "><a href="../too-many-lists/deque/iterator.html"><strong aria-hidden="true">13.5.4.</strong> 迭代器</a></li><li class="chapter-item "><a href="../too-many-lists/deque/final-code.html"><strong aria-hidden="true">13.5.5.</strong> 最终代码</a></li></ol></li><li class="chapter-item "><a href="../too-many-lists/unsafe-queue/intro.html"><strong aria-hidden="true">13.6.</strong> 不错的 unsafe 队列</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../too-many-lists/unsafe-queue/layout.html"><strong aria-hidden="true">13.6.1.</strong> 数据布局</a></li><li class="chapter-item "><a href="../too-many-lists/unsafe-queue/basics.html"><strong aria-hidden="true">13.6.2.</strong> 基本操作</a></li><li class="chapter-item "><a href="../too-many-lists/unsafe-queue/miri.html"><strong aria-hidden="true">13.6.3.</strong> Miri</a></li><li class="chapter-item "><a href="../too-many-lists/unsafe-queue/stacked-borrow.html"><strong aria-hidden="true">13.6.4.</strong> 栈借用</a></li><li class="chapter-item "><a href="../too-many-lists/unsafe-queue/testing-stacked-borrow.html"><strong aria-hidden="true">13.6.5.</strong> 测试栈借用</a></li><li class="chapter-item "><a href="../too-many-lists/unsafe-queue/layout2.html"><strong aria-hidden="true">13.6.6.</strong> 数据布局 2</a></li><li class="chapter-item "><a href="../too-many-lists/unsafe-queue/extra-junk.html"><strong aria-hidden="true">13.6.7.</strong> 额外的操作</a></li><li class="chapter-item "><a href="../too-many-lists/unsafe-queue/final-code.html"><strong aria-hidden="true">13.6.8.</strong> 最终代码</a></li></ol></li><li class="chapter-item "><a href="../too-many-lists/production-unsafe-deque/intro.html"><strong aria-hidden="true">13.7.</strong> 生产级的双向 unsafe 队列</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../too-many-lists/production-unsafe-deque/layout.html"><strong aria-hidden="true">13.7.1.</strong> 数据布局</a></li><li class="chapter-item "><a href="../too-many-lists/production-unsafe-deque/variance-and-phantomData.html"><strong aria-hidden="true">13.7.2.</strong> 型变与子类型</a></li><li class="chapter-item "><a href="../too-many-lists/production-unsafe-deque/basics.html"><strong aria-hidden="true">13.7.3.</strong> 基础结构</a></li><li class="chapter-item "><a href="../too-many-lists/production-unsafe-deque/drop-and-panic-safety.html"><strong aria-hidden="true">13.7.4.</strong> 恐慌与安全</a></li><li class="chapter-item "><a href="../too-many-lists/production-unsafe-deque/boring-combinatorics.html"><strong aria-hidden="true">13.7.5.</strong> 无聊的组合</a></li><li class="chapter-item "><a href="../too-many-lists/production-unsafe-deque/filling-in-random-bits.html"><strong aria-hidden="true">13.7.6.</strong> 其它特征</a></li><li class="chapter-item "><a href="../too-many-lists/production-unsafe-deque/testing.html"><strong aria-hidden="true">13.7.7.</strong> 测试</a></li><li class="chapter-item "><a href="../too-many-lists/production-unsafe-deque/send-sync-and-compile-tests.html"><strong aria-hidden="true">13.7.8.</strong> Send,Sync和编译测试</a></li><li class="chapter-item "><a href="../too-many-lists/production-unsafe-deque/implementing-cursors.html"><strong aria-hidden="true">13.7.9.</strong> 实现游标</a></li><li class="chapter-item "><a href="../too-many-lists/production-unsafe-deque/testing-cursors.html"><strong aria-hidden="true">13.7.10.</strong> 测试游标</a></li><li class="chapter-item "><a href="../too-many-lists/production-unsafe-deque/final-code.html"><strong aria-hidden="true">13.7.11.</strong> 最终代码</a></li></ol></li><li class="chapter-item "><a href="../too-many-lists/advanced-lists/intro.html"><strong aria-hidden="true">13.8.</strong> 使用高级技巧实现链表</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../too-many-lists/advanced-lists/double-singly.html"><strong aria-hidden="true">13.8.1.</strong> 双单向链表</a></li><li class="chapter-item "><a href="../too-many-lists/advanced-lists/stack-allocated.html"><strong aria-hidden="true">13.8.2.</strong> 栈上的链表</a></li></ol></li></ol></li><li class="chapter-item "><li class="part-title">攻克编译错误</li><li class="spacer"></li><li class="chapter-item "><a href="../compiler/intro.html"><strong aria-hidden="true">14.</strong> 征服编译错误</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../compiler/fight-with-compiler/intro.html"><strong aria-hidden="true">14.1.</strong> 对抗编译检查</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../compiler/fight-with-compiler/lifetime/intro.html"><strong aria-hidden="true">14.1.1.</strong> 生命周期</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../compiler/fight-with-compiler/lifetime/too-long1.html"><strong aria-hidden="true">14.1.1.1.</strong> 生命周期过大-01</a></li><li class="chapter-item "><a href="../compiler/fight-with-compiler/lifetime/too-long2.html"><strong aria-hidden="true">14.1.1.2.</strong> 生命周期过大-02</a></li><li class="chapter-item "><a href="../compiler/fight-with-compiler/lifetime/loop.html"><strong aria-hidden="true">14.1.1.3.</strong> 循环中的生命周期</a></li><li class="chapter-item "><a href="../compiler/fight-with-compiler/lifetime/closure-with-static.html"><strong aria-hidden="true">14.1.1.4.</strong> 闭包碰到特征对象-01</a></li></ol></li><li class="chapter-item "><a href="../compiler/fight-with-compiler/borrowing/intro.html"><strong aria-hidden="true">14.1.2.</strong> 重复借用</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../compiler/fight-with-compiler/borrowing/ref-exist-in-out-fn.html"><strong aria-hidden="true">14.1.2.1.</strong> 同时在函数内外使用引用</a></li><li class="chapter-item "><a href="../compiler/fight-with-compiler/borrowing/borrow-distinct-fields-of-struct.html"><strong aria-hidden="true">14.1.2.2.</strong> 智能指针引起的重复借用错误</a></li></ol></li><li class="chapter-item "><a href="../compiler/fight-with-compiler/unconstrained.html"><strong aria-hidden="true">14.1.3.</strong> 类型未限制(todo)</a></li><li class="chapter-item "><a href="../compiler/fight-with-compiler/phantom-data.html"><strong aria-hidden="true">14.1.4.</strong> 幽灵数据(todo)</a></li></ol></li><li class="chapter-item "><a href="../compiler/pitfalls/index.html"><strong aria-hidden="true">14.2.</strong> Rust 常见陷阱</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../compiler/pitfalls/use-vec-in-for.html"><strong aria-hidden="true">14.2.1.</strong> for 循环中使用外部数组</a></li><li class="chapter-item "><a href="../compiler/pitfalls/stack-overflow.html"><strong aria-hidden="true">14.2.2.</strong> 线程类型导致的栈溢出</a></li><li class="chapter-item "><a href="../compiler/pitfalls/arithmetic-overflow.html"><strong aria-hidden="true">14.2.3.</strong> 算术溢出导致的 panic</a></li><li class="chapter-item "><a href="../compiler/pitfalls/closure-with-lifetime.html"><strong aria-hidden="true">14.2.4.</strong> 闭包中奇怪的生命周期</a></li><li class="chapter-item "><a href="../compiler/pitfalls/the-disabled-mutability.html"><strong aria-hidden="true">14.2.5.</strong> 可变变量不可变？</a></li><li class="chapter-item "><a href="../compiler/pitfalls/multiple-mutable-references.html"><strong aria-hidden="true">14.2.6.</strong> 可变借用失败引发的深入思考</a></li><li class="chapter-item "><a href="../compiler/pitfalls/lazy-iterators.html"><strong aria-hidden="true">14.2.7.</strong> 不太勤快的迭代器</a></li><li class="chapter-item "><a href="../compiler/pitfalls/weird-ranges.html"><strong aria-hidden="true">14.2.8.</strong> 奇怪的序列 x..y</a></li><li class="chapter-item "><a href="../compiler/pitfalls/iterator-everywhere.html"><strong aria-hidden="true">14.2.9.</strong> 无处不在的迭代器</a></li><li class="chapter-item "><a href="../compiler/pitfalls/main-with-channel-blocked.html"><strong aria-hidden="true">14.2.10.</strong> 线程间传递消息导致主线程无法结束</a></li><li class="chapter-item "><a href="../compiler/pitfalls/utf8-performance.html"><strong aria-hidden="true">14.2.11.</strong> 警惕 UTF-8 引发的性能隐患</a></li></ol></li></ol></li><li class="chapter-item "><li class="part-title">性能优化</li><li class="spacer"></li><li class="chapter-item "><a href="../profiling/intro.html"><strong aria-hidden="true">15.</strong> Rust 性能优化 todo</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../profiling/memory/intro.html"><strong aria-hidden="true">15.1.</strong> 深入内存 todo</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../profiling/memory/pointer-ref.html"><strong aria-hidden="true">15.1.1.</strong> 指针和引用 todo</a></li><li class="chapter-item "><a href="../profiling/memory/uninit.html"><strong aria-hidden="true">15.1.2.</strong> 未初始化内存 todo</a></li><li class="chapter-item "><a href="../profiling/memory/allocation.html"><strong aria-hidden="true">15.1.3.</strong> 内存分配 todo</a></li><li class="chapter-item "><a href="../profiling/memory/layout.html"><strong aria-hidden="true">15.1.4.</strong> 内存布局 todo</a></li><li class="chapter-item "><a href="../profiling/memory/virtual.html"><strong aria-hidden="true">15.1.5.</strong> 虚拟内存 todo</a></li></ol></li><li class="chapter-item "><a href="../profiling/performance/intro.html"><strong aria-hidden="true">15.2.</strong> 性能调优 doing</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../profiling/performance/string.html"><strong aria-hidden="true">15.2.1.</strong> 字符串操作性能</a></li><li class="chapter-item "><a href="../profiling/performance/deep-into-move.html"><strong aria-hidden="true">15.2.2.</strong> 深入理解 move</a></li><li class="chapter-item "><a href="../profiling/performance/early-optimise.html"><strong aria-hidden="true">15.2.3.</strong> 糟糕的提前优化 todo</a></li><li class="chapter-item "><a href="../profiling/performance/clone-copy.html"><strong aria-hidden="true">15.2.4.</strong> Clone 和 Copy todo</a></li><li class="chapter-item "><a href="../profiling/performance/runtime-check.html"><strong aria-hidden="true">15.2.5.</strong> 减少 Runtime check(todo)</a></li><li class="chapter-item "><a href="../profiling/performance/cpu-cache.html"><strong aria-hidden="true">15.2.6.</strong> CPU 缓存性能优化 todo</a></li><li class="chapter-item "><a href="../profiling/performance/calculate.html"><strong aria-hidden="true">15.2.7.</strong> 计算性能优化 todo</a></li><li class="chapter-item "><a href="../profiling/performance/heap-stack.html"><strong aria-hidden="true">15.2.8.</strong> 堆和栈 todo</a></li><li class="chapter-item "><a href="../profiling/performance/allocator.html"><strong aria-hidden="true">15.2.9.</strong> 内存 allocator todo</a></li><li class="chapter-item "><a href="../profiling/performance/tools.html"><strong aria-hidden="true">15.2.10.</strong> 常用性能测试工具 todo</a></li><li class="chapter-item "><a href="../profiling/performance/enum.html"><strong aria-hidden="true">15.2.11.</strong> Enum 内存优化 todo</a></li></ol></li><li class="chapter-item "><a href="../profiling/compiler/intro.html"><strong aria-hidden="true">15.3.</strong> 编译优化 todo</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../profiling/compiler/llvm.html"><strong aria-hidden="true">15.3.1.</strong> LLVM todo</a></li><li class="chapter-item "><a href="../profiling/compiler/attributes.html"><strong aria-hidden="true">15.3.2.</strong> 常见属性标记 todo</a></li><li class="chapter-item "><a href="../profiling/compiler/speed-up.html"><strong aria-hidden="true">15.3.3.</strong> 提升编译速度 todo</a></li><li class="chapter-item "><a href="../profiling/compiler/optimization/intro.html"><strong aria-hidden="true">15.3.4.</strong> 编译器优化 todo</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../profiling/compiler/optimization/option.html"><strong aria-hidden="true">15.3.4.1.</strong> Option 枚举 todo</a></li></ol></li></ol></li></ol></li><li class="chapter-item "><li class="part-title">附录</li><li class="spacer"></li><li class="chapter-item "><div><strong aria-hidden="true">16.</strong> Appendix</div><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../appendix/keywords.html"><strong aria-hidden="true">16.1.</strong> 关键字</a></li><li class="chapter-item "><a href="../appendix/operators.html"><strong aria-hidden="true">16.2.</strong> 运算符与符号</a></li><li class="chapter-item "><a href="../appendix/expressions.html"><strong aria-hidden="true">16.3.</strong> 表达式</a></li><li class="chapter-item "><a href="../appendix/derive.html"><strong aria-hidden="true">16.4.</strong> 派生特征 trait</a></li><li class="chapter-item "><a href="../appendix/prelude.html"><strong aria-hidden="true">16.5.</strong> prelude 模块 todo</a></li><li class="chapter-item "><a href="../appendix/rust-version.html"><strong aria-hidden="true">16.6.</strong> Rust 版本说明</a></li><li class="chapter-item "><a href="../appendix/rust-versions/intro.html"><strong aria-hidden="true">16.7.</strong> Rust 历次版本更新解读</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../appendix/rust-versions/1.58.html"><strong aria-hidden="true">16.7.1.</strong> 1.58</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.59.html"><strong aria-hidden="true">16.7.2.</strong> 1.59</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.60.html"><strong aria-hidden="true">16.7.3.</strong> 1.60</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.61.html"><strong aria-hidden="true">16.7.4.</strong> 1.61</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.62.html"><strong aria-hidden="true">16.7.5.</strong> 1.62</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.63.html"><strong aria-hidden="true">16.7.6.</strong> 1.63</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.64.html"><strong aria-hidden="true">16.7.7.</strong> 1.64</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.65.html"><strong aria-hidden="true">16.7.8.</strong> 1.65</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.66.html"><strong aria-hidden="true">16.7.9.</strong> 1.66</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.67.html"><strong aria-hidden="true">16.7.10.</strong> 1.67</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.68.html"><strong aria-hidden="true">16.7.11.</strong> 1.68</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.69.html"><strong aria-hidden="true">16.7.12.</strong> 1.69</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.70.html"><strong aria-hidden="true">16.7.13.</strong> 1.70</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.71.html"><strong aria-hidden="true">16.7.14.</strong> 1.71</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.72.html"><strong aria-hidden="true">16.7.15.</strong> 1.72</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.73.html"><strong aria-hidden="true">16.7.16.</strong> 1.73</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.74.html"><strong aria-hidden="true">16.7.17.</strong> 1.74</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.75.html"><strong aria-hidden="true">16.7.18.</strong> 1.75</a></li><li class="chapter-item "><a href="../appendix/rust-versions/1.76.html"><strong aria-hidden="true">16.7.19.</strong> 1.76</a></li></ol></li></ol></li></ol>
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<main>
<h1 id="格式化输出"><a class="header" href="#格式化输出">格式化输出</a></h1>
<p>提到格式化输出，可能很多人立刻就想到 <code>&quot;{}&quot;</code>，但是 Rust 能做到的远比这个多的多，本章节我们将深入讲解格式化输出的各个方面。</p>
<h2 id="满分初印象"><a class="header" href="#满分初印象">满分初印象</a></h2>
<p>先来一段代码，看看格式化输出的初印象：</p>
<pre><pre class="playground"><code class="language-rust edition2021"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>println!(&quot;Hello&quot;); // =&gt; &quot;Hello&quot;
println!(&quot;Hello, {}!&quot;, &quot;world&quot;); // =&gt; &quot;Hello, world!&quot;
println!(&quot;The number is {}&quot;, 1); // =&gt; &quot;The number is 1&quot;
println!(&quot;{:?}&quot;, (3, 4)); // =&gt; &quot;(3, 4)&quot;
println!(&quot;{value}&quot;, value=4); // =&gt; &quot;4&quot;
println!(&quot;{} {}&quot;, 1, 2); // =&gt; &quot;1 2&quot;
println!(&quot;{:04}&quot;, 42); // =&gt; &quot;0042&quot; with leading zeros
<span class="boring">}</span></code></pre></pre>
<p>可以看到 <code>println!</code> 宏接受的是可变参数，第一个参数是一个字符串常量，它表示最终输出字符串的格式，包含其中形如 <code>{}</code> 的符号是<strong>占位符</strong>，会被 <code>println!</code> 后面的参数依次替换。</p>
<h2 id="printprintlnformat"><a class="header" href="#printprintlnformat"><code>print!</code>，<code>println!</code>，<code>format!</code></a></h2>
<p>它们是 Rust 中用来格式化输出的三大金刚，用途如下：</p>
<ul>
<li><code>print!</code> 将格式化文本输出到标准输出，不带换行符</li>
<li><code>println!</code> 同上，但是在行的末尾添加换行符</li>
<li><code>format!</code> 将格式化文本输出到 <code>String</code> 字符串</li>
</ul>
<p>在实际项目中，最常用的是 <code>println!</code> 及 <code>format!</code>，前者常用来调试输出，后者常用来生成格式化的字符串：</p>
<pre><pre class="playground"><code class="language-rust edition2021">fn main() {
let s = &quot;hello&quot;;
println!(&quot;{}, world&quot;, s);
let s1 = format!(&quot;{}, world&quot;, s);
print!(&quot;{}&quot;, s1);
print!(&quot;{}\n&quot;, &quot;!&quot;);
}</code></pre></pre>
<p>其中，<code>s1</code> 是通过 <code>format!</code> 生成的 <code>String</code> 字符串，最终输出如下：</p>
<pre><code class="language-console">hello, world
hello, world!
</code></pre>
<h4 id="eprinteprintln"><a class="header" href="#eprinteprintln"><code>eprint!</code>，<code>eprintln!</code></a></h4>
<p>除了三大金刚外，还有两大护法，使用方式跟 <code>print!</code>，<code>println!</code> 很像，但是它们输出到标准错误输出：</p>
<pre><pre class="playground"><code class="language-rust edition2021"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>eprintln!(&quot;Error: Could not complete task&quot;)
<span class="boring">}</span></code></pre></pre>
<p>它们仅应该被用于输出错误信息和进度信息，其它场景都应该使用 <code>print!</code> 系列。</p>
<h2 id="-与"><a class="header" href="#-与">{} 与</a></h2>
<p>与其它语言常用的 <code>%d</code>，<code>%s</code> 不同，Rust 特立独行地选择了 <code>{}</code> 作为格式化占位符（说到这个，有点想吐槽下，Rust 中自创的概念其实还挺多的，真不知道该夸奖还是该吐槽-,-），事实证明，这种选择非常正确，它帮助用户减少了很多使用成本，你无需再为特定的类型选择特定的占位符，统一用 <code>{}</code> 来替代即可，剩下的类型推导等细节只要交给 Rust 去做。</p>
<p>与 <code>{}</code> 类似，<code>{:?}</code> 也是占位符：</p>
<ul>
<li><code>{}</code> 适用于实现了 <code>std::fmt::Display</code> 特征的类型，用来以更优雅、更友好的方式格式化文本，例如展示给用户</li>
<li><code>{:?}</code> 适用于实现了 <code>std::fmt::Debug</code> 特征的类型，用于调试场景</li>
</ul>
<p>其实两者的选择很简单，当你在写代码需要调试时，使用 <code>{:?}</code>，剩下的场景，选择 <code>{}</code>。</p>
<h4 id="debug-特征"><a class="header" href="#debug-特征"><code>Debug</code> 特征</a></h4>
<p>事实上，为了方便我们调试，大多数 Rust 类型都实现了 <code>Debug</code> 特征或者支持派生该特征：</p>
<pre><pre class="playground"><code class="language-rust edition2021">#[derive(Debug)]
struct Person {
name: String,
age: u8
}
fn main() {
let i = 3.1415926;
let s = String::from(&quot;hello&quot;);
let v = vec![1, 2, 3];
let p = Person{name: &quot;sunface&quot;.to_string(), age: 18};
println!(&quot;{:?}, {:?}, {:?}, {:?}&quot;, i, s, v, p);
}</code></pre></pre>
<p>对于数值、字符串、数组，可以直接使用 <code>{:?}</code> 进行输出，但是对于结构体，需要<a href="https://course.rs/appendix/derive.html">派生<code>Debug</code></a>特征后，才能进行输出，总之很简单。</p>
<h4 id="display-特征"><a class="header" href="#display-特征"><code>Display</code> 特征</a></h4>
<p>与大部分类型实现了 <code>Debug</code> 不同，实现了 <code>Display</code> 特征的 Rust 类型并没有那么多，往往需要我们自定义想要的格式化方式：</p>
<pre><pre class="playground"><code class="language-rust edition2021"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>let i = 3.1415926;
let s = String::from(&quot;hello&quot;);
let v = vec![1, 2, 3];
let p = Person {
name: &quot;sunface&quot;.to_string(),
age: 18,
};
println!(&quot;{}, {}, {}, {}&quot;, i, s, v, p);
<span class="boring">}</span></code></pre></pre>
<p>运行后可以看到 <code>v</code> 和 <code>p</code> 都无法通过编译，因为没有实现 <code>Display</code> 特征，但是你又不能像派生 <code>Debug</code> 一般派生 <code>Display</code>，只能另寻他法：</p>
<ul>
<li>使用 <code>{:?}</code> 或 <code>{:#?}</code></li>
<li>为自定义类型实现 <code>Display</code> 特征</li>
<li>使用 <code>newtype</code> 为外部类型实现 <code>Display</code> 特征</li>
</ul>
<p>下面来一一看看这三种方式。</p>
<h4 id=""><a class="header" href="#"></a></h4>
<p><code>{:#?}</code> 与 <code>{:?}</code> 几乎一样，唯一的区别在于它能更优美地输出内容：</p>
<pre><code class="language-console">// {:?}
[1, 2, 3], Person { name: &quot;sunface&quot;, age: 18 }
// {:#?}
[
1,
2,
3,
], Person {
name: &quot;sunface&quot;,
}
</code></pre>
<p>因此对于 <code>Display</code> 不支持的类型，可以考虑使用 <code>{:#?}</code> 进行格式化，虽然理论上它更适合进行调试输出。</p>
<h4 id="为自定义类型实现-display-特征"><a class="header" href="#为自定义类型实现-display-特征">为自定义类型实现 <code>Display</code> 特征</a></h4>
<p>如果你的类型是定义在当前作用域中的，那么可以为其实现 <code>Display</code> 特征，即可用于格式化输出：</p>
<pre><pre class="playground"><code class="language-rust edition2021">struct Person {
name: String,
age: u8,
}
use std::fmt;
impl fmt::Display for Person {
fn fmt(&amp;self, f: &amp;mut fmt::Formatter) -&gt; fmt::Result {
write!(
f,
&quot;大佬在上，请受我一拜，小弟姓名{}，年芳{}，家里无田又无车，生活苦哈哈&quot;,
self.name, self.age
)
}
}
fn main() {
let p = Person {
name: &quot;sunface&quot;.to_string(),
age: 18,
};
println!(&quot;{}&quot;, p);
}</code></pre></pre>
<p>如上所示，只要实现 <code>Display</code> 特征中的 <code>fmt</code> 方法，即可为自定义结构体 <code>Person</code> 添加自定义输出：</p>
<pre><code class="language-console">大佬在上，请受我一拜，小弟姓名sunface，年芳18，家里无田又无车，生活苦哈哈
</code></pre>
<h4 id="为外部类型实现-display-特征"><a class="header" href="#为外部类型实现-display-特征">为外部类型实现 <code>Display</code> 特征</a></h4>
<p>在 Rust 中，无法直接为外部类型实现外部特征，但是可以使用<a href="https://course.rs/advance/into-types/custom-type.html#newtype"><code>newtype</code></a>解决此问题：</p>
<pre><pre class="playground"><code class="language-rust edition2021">struct Array(Vec&lt;i32&gt;);
use std::fmt;
impl fmt::Display for Array {
fn fmt(&amp;self, f: &amp;mut fmt::Formatter) -&gt; fmt::Result {
write!(f, &quot;数组是：{:?}&quot;, self.0)
}
}
fn main() {
let arr = Array(vec![1, 2, 3]);
println!(&quot;{}&quot;, arr);
}</code></pre></pre>
<p><code>Array</code> 就是我们的 <code>newtype</code>，它将想要格式化输出的 <code>Vec</code> 包裹在内，最后只要为 <code>Array</code> 实现 <code>Display</code> 特征，即可进行格式化输出：</p>
<pre><code class="language-console">数组是：[1, 2, 3]
</code></pre>
<p>至此，关于 <code>{}</code> 与 <code>{:?}</code> 的内容已介绍完毕，下面让我们正式开始格式化输出的旅程。</p>
<h2 id="位置参数"><a class="header" href="#位置参数">位置参数</a></h2>
<p>除了按照依次顺序使用值去替换占位符之外，还能让指定位置的参数去替换某个占位符，例如 <code>{1}</code>，表示用第二个参数替换该占位符(索引从 0 开始)：</p>
<pre><pre class="playground"><code class="language-rust edition2021">fn main() {
println!(&quot;{}{}&quot;, 1, 2); // =&gt;&quot;12&quot;
println!(&quot;{1}{0}&quot;, 1, 2); // =&gt;&quot;21&quot;
// =&gt; Alice, this is Bob. Bob, this is Alice
println!(&quot;{0}, this is {1}. {1}, this is {0}&quot;, &quot;Alice&quot;, &quot;Bob&quot;);
println!(&quot;{1}{}{0}{}&quot;, 1, 2); // =&gt; 2112
}</code></pre></pre>
<h2 id="具名参数"><a class="header" href="#具名参数">具名参数</a></h2>
<p>除了像上面那样指定位置外，我们还可以为参数指定名称：</p>
<pre><pre class="playground"><code class="language-rust edition2021">fn main() {
println!(&quot;{argument}&quot;, argument = &quot;test&quot;); // =&gt; &quot;test&quot;
println!(&quot;{name} {}&quot;, 1, name = 2); // =&gt; &quot;2 1&quot;
println!(&quot;{a} {c} {b}&quot;, a = &quot;a&quot;, b = 'b', c = 3); // =&gt; &quot;a 3 b&quot;
}</code></pre></pre>
<p>需要注意的是：<strong>带名称的参数必须放在不带名称参数的后面</strong>，例如下面代码将报错：</p>
<pre><pre class="playground"><code class="language-rust edition2021"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>println!(&quot;{abc} {1}&quot;, abc = &quot;def&quot;, 2);
<span class="boring">}</span></code></pre></pre>
<pre><pre class="playground"><code class="language-rust edition2021"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>error: positional arguments cannot follow named arguments
--&gt; src/main.rs:4:36
|
4 | println!(&quot;{abc} {1}&quot;, abc = &quot;def&quot;, 2);
| ----- ^ positional arguments must be before named arguments
| |
| named argument
<span class="boring">}</span></code></pre></pre>
<h2 id="格式化参数"><a class="header" href="#格式化参数">格式化参数</a></h2>
<p>格式化输出，意味着对输出格式会有更多的要求，例如只输出浮点数的小数点后两位：</p>
<pre><pre class="playground"><code class="language-rust edition2021">fn main() {
let v = 3.1415926;
// Display =&gt; 3.14
println!(&quot;{:.2}&quot;, v);
// Debug =&gt; 3.14
println!(&quot;{:.2?}&quot;, v);
}</code></pre></pre>
<p>上面代码只输出小数点后两位。同时我们还展示了 <code>{}</code> 和 <code>{:?}</code> 的用法，后面如无特殊区别，就只针对 <code>{}</code> 提供格式化参数说明。</p>
<p>接下来，让我们一起来看看 Rust 中有哪些格式化参数。</p>
<h3 id="宽度"><a class="header" href="#宽度">宽度</a></h3>
<p>宽度用来指示输出目标的长度，如果长度不够，则进行填充和对齐：</p>
<h4 id="字符串填充"><a class="header" href="#字符串填充">字符串填充</a></h4>
<p>字符串格式化默认使用空格进行填充，并且进行左对齐。</p>
<pre><pre class="playground"><code class="language-rust edition2021">fn main() {
//-----------------------------------
// 以下全部输出 &quot;Hello x !&quot;
// 为&quot;x&quot;后面填充空格，补齐宽度5
println!(&quot;Hello {:5}!&quot;, &quot;x&quot;);
// 使用参数5来指定宽度
println!(&quot;Hello {:1$}!&quot;, &quot;x&quot;, 5);
// 使用x作为占位符输出内容，同时使用5作为宽度
println!(&quot;Hello {1:0$}!&quot;, 5, &quot;x&quot;);
// 使用有名称的参数作为宽度
println!(&quot;Hello {:width$}!&quot;, &quot;x&quot;, width = 5);
//-----------------------------------
// 使用参数5为参数x指定宽度，同时在结尾输出参数5 =&gt; Hello x !5
println!(&quot;Hello {:1$}!{}&quot;, &quot;x&quot;, 5);
}</code></pre></pre>
<h4 id="数字填充符号和-0"><a class="header" href="#数字填充符号和-0">数字填充:符号和 0</a></h4>
<p>数字格式化默认也是使用空格进行填充，但与字符串左对齐不同的是，数字是右对齐。</p>
<pre><pre class="playground"><code class="language-rust edition2021">fn main() {
// 宽度是5 =&gt; Hello 5!
println!(&quot;Hello {:5}!&quot;, 5);
// 显式的输出正号 =&gt; Hello +5!
println!(&quot;Hello {:+}!&quot;, 5);
// 宽度5，使用0进行填充 =&gt; Hello 00005!
println!(&quot;Hello {:05}!&quot;, 5);
// 负号也要占用一位宽度 =&gt; Hello -0005!
println!(&quot;Hello {:05}!&quot;, -5);
}</code></pre></pre>
<h3 id="对齐"><a class="header" href="#对齐">对齐</a></h3>
<pre><pre class="playground"><code class="language-rust edition2021">fn main() {
// 以下全部都会补齐5个字符的长度
// 左对齐 =&gt; Hello x !
println!(&quot;Hello {:&lt;5}!&quot;, &quot;x&quot;);
// 右对齐 =&gt; Hello x!
println!(&quot;Hello {:&gt;5}!&quot;, &quot;x&quot;);
// 居中对齐 =&gt; Hello x !
println!(&quot;Hello {:^5}!&quot;, &quot;x&quot;);
// 对齐并使用指定符号填充 =&gt; Hello x&amp;&amp;&amp;&amp;!
// 指定符号填充的前提条件是必须有对齐字符
println!(&quot;Hello {:&amp;&lt;5}!&quot;, &quot;x&quot;);
}</code></pre></pre>
<h3 id="精度"><a class="header" href="#精度">精度</a></h3>
<p>精度可以用于控制浮点数的精度或者字符串的长度</p>
<pre><pre class="playground"><code class="language-rust edition2021">fn main() {
let v = 3.1415926;
// 保留小数点后两位 =&gt; 3.14
println!(&quot;{:.2}&quot;, v);
// 带符号保留小数点后两位 =&gt; +3.14
println!(&quot;{:+.2}&quot;, v);
// 不带小数 =&gt; 3
println!(&quot;{:.0}&quot;, v);
// 通过参数来设定精度 =&gt; 3.1416，相当于{:.4}
println!(&quot;{:.1$}&quot;, v, 4);
let s = &quot;hi我是Sunface孙飞&quot;;
// 保留字符串前三个字符 =&gt; hi我
println!(&quot;{:.3}&quot;, s);
// {:.*}接收两个参数，第一个是精度，第二个是被格式化的值 =&gt; Hello abc!
println!(&quot;Hello {:.*}!&quot;, 3, &quot;abcdefg&quot;);
}</code></pre></pre>
<h3 id="进制"><a class="header" href="#进制">进制</a></h3>
<p>可以使用 <code>#</code> 号来控制数字的进制输出：</p>
<ul>
<li><code>#b</code>, 二进制</li>
<li><code>#o</code>, 八进制</li>
<li><code>#x</code>, 小写十六进制</li>
<li><code>#X</code>, 大写十六进制</li>
<li><code>x</code>, 不带前缀的小写十六进制</li>
</ul>
<pre><pre class="playground"><code class="language-rust edition2021">fn main() {
// 二进制 =&gt; 0b11011!
println!(&quot;{:#b}!&quot;, 27);
// 八进制 =&gt; 0o33!
println!(&quot;{:#o}!&quot;, 27);
// 十进制 =&gt; 27!
println!(&quot;{}!&quot;, 27);
// 小写十六进制 =&gt; 0x1b!
println!(&quot;{:#x}!&quot;, 27);
// 大写十六进制 =&gt; 0x1B!
println!(&quot;{:#X}!&quot;, 27);
// 不带前缀的十六进制 =&gt; 1b!
println!(&quot;{:x}!&quot;, 27);
// 使用0填充二进制，宽度为10 =&gt; 0b00011011!
println!(&quot;{:#010b}!&quot;, 27);
}</code></pre></pre>
<h3 id="指数"><a class="header" href="#指数">指数</a></h3>
<pre><pre class="playground"><code class="language-rust edition2021">fn main() {
println!(&quot;{:2e}&quot;, 1000000000); // =&gt; 1e9
println!(&quot;{:2E}&quot;, 1000000000); // =&gt; 1E9
}</code></pre></pre>
<h3 id="指针地址"><a class="header" href="#指针地址">指针地址</a></h3>
<pre><pre class="playground"><code class="language-rust edition2021"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>let v= vec![1, 2, 3];
println!(&quot;{:p}&quot;, v.as_ptr()) // =&gt; 0x600002324050
<span class="boring">}</span></code></pre></pre>
<h3 id="转义"><a class="header" href="#转义">转义</a></h3>
<p>有时需要输出 <code>{</code>和<code>}</code>，但这两个字符是特殊字符，需要进行转义：</p>
<pre><pre class="playground"><code class="language-rust edition2021">fn main() {
// &quot;{{&quot; 转义为 '{' &quot;}}&quot; 转义为 '}' &quot;\&quot;&quot; 转义为 '&quot;'
// =&gt; Hello &quot;{World}&quot;
println!(&quot; Hello \&quot;{{World}}\&quot; &quot;);
// 下面代码会报错，因为占位符{}只有一个右括号}，左括号被转义成字符串的内容
// println!(&quot; {{ Hello } &quot;);
// 也不可使用 '\' 来转义 &quot;{}&quot;
// println!(&quot; \{ Hello \} &quot;)
}</code></pre></pre>
<h2 id="在格式化字符串时捕获环境中的值rust-158-新增"><a class="header" href="#在格式化字符串时捕获环境中的值rust-158-新增">在格式化字符串时捕获环境中的值（Rust 1.58 新增）</a></h2>
<p>在以前，想要输出一个函数的返回值，你需要这么做：</p>
<pre><pre class="playground"><code class="language-rust edition2021">fn get_person() -&gt; String {
String::from(&quot;sunface&quot;)
}
fn main() {
let p = get_person();
println!(&quot;Hello, {}!&quot;, p); // implicit position
println!(&quot;Hello, {0}!&quot;, p); // explicit index
println!(&quot;Hello, {person}!&quot;, person = p);
}</code></pre></pre>
<p>问题倒也不大，但是一旦格式化字符串长了后，就会非常冗余，而在 1.58 后，我们可以这么写：</p>
<pre><pre class="playground"><code class="language-rust edition2021">fn get_person() -&gt; String {
String::from(&quot;sunface&quot;)
}
fn main() {
let person = get_person();
println!(&quot;Hello, {person}!&quot;);
}</code></pre></pre>
<p>是不是清晰、简洁了很多？甚至还可以将环境中的值用于格式化参数:</p>
<pre><pre class="playground"><code class="language-rust edition2021"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>let (width, precision) = get_format();
for (name, score) in get_scores() {
println!(&quot;{name}: {score:width$.precision$}&quot;);
}
<span class="boring">}</span></code></pre></pre>
<p>但也有局限，它只能捕获普通的变量，对于更复杂的类型（例如表达式），可以先将它赋值给一个变量或使用以前的 <code>name = expression</code> 形式的格式化参数。
目前除了 <code>panic!</code> 外，其它接收格式化参数的宏，都可以使用新的特性。对于 <code>panic!</code> 而言，如果还在使用 <code>2015版本</code> 或 <code>2018版本</code>，那 <code>panic!(&quot;{ident}&quot;)</code> 依然会被当成 正常的字符串来处理，同时编译器会给予 <code>warn</code> 提示。而对于 <code>2021版本</code> ，则可以正常使用:</p>
<pre><pre class="playground"><code class="language-rust edition2021">fn get_person() -&gt; String {
String::from(&quot;sunface&quot;)
}
fn main() {
let person = get_person();
panic!(&quot;Hello, {person}!&quot;);
}</code></pre></pre>
<p>输出:</p>
<pre><code class="language-console">thread 'main' panicked at 'Hello, sunface!', src/main.rs:6:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
</code></pre>
<h2 id="课后练习"><a class="header" href="#课后练习">课后练习</a></h2>
<blockquote>
<p><a href="https://practice-zh.course.rs/formatted-output.html">Rust By Practice</a>，支持代码在线编辑和运行，并提供详细的习题解答。（本节暂无习题解答）</p>
</blockquote>
<h2 id="总结"><a class="header" href="#总结">总结</a></h2>
<p>把这些格式化都牢记在脑中是不太现实的，也没必要，我们要做的就是知道 Rust 支持相应的格式化输出，在需要之时，读者再来查阅本文即可。</p>
<p>还是那句话，<a href="https://github.com/sunface/rust-course">&lt;&lt;Rust 语言圣经&gt;&gt;</a>不仅仅是 Rust 学习书籍，还是一本厚重的工具书！</p>
<p>至此，Rust 的基础内容学习已经全部完成，下面我们将学习 Rust 的高级进阶内容，正式开启你的高手之路。</p>
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