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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">Xobserve: 一切皆可观测</a></li><li class="chapter-item affix "><a href="../../../beat-ai.html">BeatAI: 工程师 AI 入门圣经</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 "><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 "><a href="../../../basic/formatted-output.html"><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 expanded "><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 expanded "><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 expanded "><a href="../../../cargo/reference/features/intro.html" class="active"><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><li class="chapter-item "><a href="../../../appendix/rust-versions/1.77.html"><strong aria-hidden="true">16.7.20.</strong> 1.77</a></li><li class="chapter-item "><a href="../../../appendix/rust-versions/1.78.html"><strong aria-hidden="true">16.7.21.</strong> 1.78</a></li><li class="chapter-item "><a href="../../../appendix/rust-versions/1.79.html"><strong aria-hidden="true">16.7.22.</strong> 1.79</a></li><li class="chapter-item "><a href="../../../appendix/rust-versions/1.80.html"><strong aria-hidden="true">16.7.23.</strong> 1.80</a></li><li class="chapter-item "><a href="../../../appendix/rust-versions/1.81.html"><strong aria-hidden="true">16.7.24.</strong> 1.81</a></li><li class="chapter-item "><a href="../../../appendix/rust-versions/1.82.html"><strong aria-hidden="true">16.7.25.</strong> 1.82</a></li></ol></li></ol></li></ol>
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<main>
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<h1 id="条件编译-features"><a class="header" href="#条件编译-features">条件编译 Features</a></h1>
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<p><code>Cargo Feature</code> 是非常强大的机制，可以为大家提供<a href="https://doc.rust-lang.org/stable/reference/conditional-compilation.html">条件编译</a>和可选依赖的高级特性。</p>
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<h2 id="features"><a class="header" href="#features">[features]</a></h2>
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<p><code>Feature</code> 可以通过 <code>Cargo.toml</code> 中的 <code>[features]</code> 部分来定义：其中每个 <code>feature</code> 通过列表的方式指定了它所能启用的其他 <code>feature</code> 或可选依赖。</p>
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<p>假设我们有一个 2D 图像处理库，然后该库所支持的图片格式可以通过以下方式启用：</p>
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<pre><code class="language-toml">[features]
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# 定义一个 feature : webp, 但它并没有启用其它 feature
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webp = []
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</code></pre>
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<p>当定义了 <code>webp</code> 后，我们就可以在代码中通过 <a href="https://doc.rust-lang.org/stable/reference/conditional-compilation.html"><code>cfg</code> 表达式</a>来进行条件编译。例如项目中的 <code>lib.rs</code> 可以使用以下代码对 <code>webp</code> 模块进行条件引入:</p>
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<pre><code class="language-toml">#[cfg(feature = "webp")]
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pub mod webp;
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</code></pre>
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<p><code>#[cfg(feature = "webp")]</code> 的含义是：只有在 <code>webp</code> feature 被定义后，以下的 <code>webp</code> 模块才能被引入进来。由于我们之前在 <code>[features]</code> 里定义了 <code>webp</code>，因此以上代码的 <code>webp</code> 模块会被成功引入。</p>
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<p>在 <code>Cargo.toml</code> 中定义的 <code>feature</code> 会被 <code>Cargo</code> 通过命令行参数 <code>--cfg</code> 传给 <code>rustc</code>，最终由后者完成编译：例如，定义 "hello" 和 "hi" 两个 <code>feature</code>，等价于 <code>rustc --cfg 'feature="hello"' --cfg 'feature="hi" ...'</code>。若项目中的代码想要测试 <code>feature</code> 是否存在，可以使用 <a href="https://doc.rust-lang.org/stable/reference/conditional-compilation.html#the-cfg-attribute"><code>cfg</code> 属性</a>或 <a href="https://doc.rust-lang.org/stable/std/macro.cfg.html"><code>cfg</code> 宏</a>。</p>
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<p>之前我们提到了一个 <code>feature</code> 还可以开启其他 <code>feature</code>，举个例子，例如 ICO 图片格式包含 BMP 和 PNG 格式，因此当 <code>ico</code> 被启用后，它还得确保启用 <code>bmp</code> 和 <code>png</code> ：</p>
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<pre><code class="language-toml">[features]
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bmp = []
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png = []
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ico = ["bmp", "png"]
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webp = []
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</code></pre>
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<p>对此，我们可以理解为： <strong><code>bmp</code> 和 <code>png</code> 是开启 <code>ico</code> 的先决条件</strong>（注：开启 <code>ico</code>，会自动开启 <code>bmp</code>, <code>png</code>）。</p>
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<p>Feature 名称可以包含来自 <a href="">Unicode XID standard</a> 定义的字母，允许使用 <code>_</code> 或 <code>0-9</code> 的数字作为起始字符，在起始字符后，还可以使用 <code>-</code>、<code>+</code> 或 <code>.</code> 。</p>
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<p>但是我们<strong>还是推荐按照 crates.io 的方式来设置 Feature 名称</strong> : <code>crate.io</code> 要求名称只能由 ASCII 字母数字、<code>_</code>、<code>-</code> 或 <code>+</code> 组成。</p>
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<h2 id="default-feature"><a class="header" href="#default-feature">default feature</a></h2>
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<p>默认情况下，所有的 <code>feature</code> 都会被自动禁用，可以通过 <code>default</code> 来启用它们：</p>
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<pre><code class="language-toml">[features]
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default = ["ico", "webp"]
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bmp = []
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png = []
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ico = ["bmp", "png"]
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webp = []
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</code></pre>
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<p>使用如上配置的项目被构建时，<code>default</code> feature 首先会被启用，然后它接着启用了 <code>ico</code> 和 <code>webp</code> feature，当然我们还可以关闭 <code>default</code>：</p>
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<ul>
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<li><code>--no-default-features</code> 命令行参数可以禁用 <code>default</code> feature</li>
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<li><code>default-features = false</code> 选项可以在依赖声明中指定</li>
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</ul>
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<blockquote>
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<p>当你要去改变某个依赖库的 <code>default</code> 启用的 feature 列表时(例如觉得该库引入的 feature 过多，导致最终编译出的文件过大)，需要格外的小心，因为这可能会导致某些功能的缺失</p>
|
|
|
</blockquote>
|
|
|
<h2 id="可选依赖"><a class="header" href="#可选依赖">可选依赖</a></h2>
|
|
|
<p>当依赖被标记为 "可选 optional" 时，意味着它默认不会被编译。假设我们的 2D 图片处理库需要用到一个外部的包来处理 GIF 图片：</p>
|
|
|
<pre><code class="language-toml">[dependencies]
|
|
|
gif = { version = "0.11.1", optional = true }
|
|
|
</code></pre>
|
|
|
<p><strong>这种可选依赖的写法会自动定义一个与依赖同名的 feature，也就是 <code>gif</code> feature</strong>，这样一来，当我们启用 <code>gif</code> feature 时，该依赖库也会被自动引入并启用：例如通过 <code>--features gif</code> 的方式启用 feature 。</p>
|
|
|
<blockquote>
|
|
|
<p>注意：目前来说，<code>[feature]</code> 中定义的 feature 还不能与已引入的依赖库同名。但是在 <code>nightly</code> 中已经提供了实验性的功能用于改变这一点: <a href="https://doc.rust-lang.org/stable/cargo/reference/unstable.html#namespaced-features">namespaced features</a></p>
|
|
|
</blockquote>
|
|
|
<p>当然，<strong>我们还可以通过显式定义 feature 的方式来启用这些可选依赖库</strong>，例如为了支持 AVIF 图片格式，我们需要引入两个依赖包，由于 <code>avif</code> 是通过 feature 引入的可选格式，因此它依赖的两个包也必须声明为可选的:</p>
|
|
|
<pre><code class="language-toml">[dependencies]
|
|
|
ravif = { version = "0.6.3", optional = true }
|
|
|
rgb = { version = "0.8.25", optional = true }
|
|
|
|
|
|
[features]
|
|
|
avif = ["ravif", "rgb"]
|
|
|
</code></pre>
|
|
|
<p>之后，<code>avif</code> feature 一旦被启用，那这两个依赖库也将自动被引入。</p>
|
|
|
<blockquote>
|
|
|
<p>注意：我们之前也讲过条件引入依赖的方法，那就是使用<a href="https://course.rs/cargo/reference/specify-deps.html#%E6%A0%B9%E6%8D%AE%E5%B9%B3%E5%8F%B0%E5%BC%95%E5%85%A5%E4%BE%9D%E8%B5%96">平台相关的依赖</a>，与基于 feature 的可选依赖不同，它们是基于特定平台的可选依赖</p>
|
|
|
</blockquote>
|
|
|
<h2 id="依赖库自身的-feature"><a class="header" href="#依赖库自身的-feature">依赖库自身的 feature</a></h2>
|
|
|
<p>就像我们的项目可以定义 <code>feature</code> 一样，依赖库也可以定义它自己的 <code>feature</code>，也有需要启用的 <code>feature</code> 列表，当引入该依赖库时，我们可以通过以下方式为其启用相关的 <code>features</code> :</p>
|
|
|
<pre><code class="language-toml">[dependencies]
|
|
|
serde = { version = "1.0.118", features = ["derive"] }
|
|
|
</code></pre>
|
|
|
<p>以上配置为 <code>serde</code> 依赖开启了 <code>derive</code> feature，还可以通过 <code>default-features = false</code> 来禁用依赖库的 <code>default</code> feature :</p>
|
|
|
<pre><code class="language-toml">[dependencies]
|
|
|
flate2 = { version = "1.0.3", default-features = false, features = ["zlib"] }
|
|
|
</code></pre>
|
|
|
<p>这里我们禁用了 <code>flate2</code> 的 <code>default</code> feature，但又手动为它启用了 <code>zlib</code> feature。</p>
|
|
|
<blockquote>
|
|
|
<p>注意：这种方式未必能成功禁用 <code>default</code>，原因是可能会有其它依赖也引入了 <code>flate2</code>，并且没有对 <code>default</code> 进行禁用，那此时 <code>default</code> 依然会被启用。</p>
|
|
|
<p>查看下文的 <a href="#feature-%E5%90%8C%E4%B8%80%E5%8C%96">feature 同一化</a> 获取更多信息</p>
|
|
|
</blockquote>
|
|
|
<p>除此之外，还能通过下面的方式来间接开启依赖库的 feature :</p>
|
|
|
<pre><code class="language-toml">[dependencies]
|
|
|
jpeg-decoder = { version = "0.1.20", default-features = false }
|
|
|
|
|
|
[features]
|
|
|
# Enables parallel processing support by enabling the "rayon" feature of jpeg-decoder.
|
|
|
parallel = ["jpeg-decoder/rayon"]
|
|
|
</code></pre>
|
|
|
<p>如上所示，我们定义了一个 <code>parallel</code> feature，同时为其启用了 <code>jpeg-decoder</code> 依赖的 <code>rayon</code> feature。</p>
|
|
|
<blockquote>
|
|
|
<p>注意: 上面的 "package-name/feature-name" 语法形式不仅会开启指定依赖的指定 feature，若该依赖是可选依赖，那还会自动将其引入</p>
|
|
|
<p>在 <code>nightly</code> 版本中，可以对这种行为进行禁用：<a href="%22package-name/feature-name%22">weak dependency features</a></p>
|
|
|
</blockquote>
|
|
|
<h2 id="通过命令行参数启用-feature"><a class="header" href="#通过命令行参数启用-feature">通过命令行参数启用 feature</a></h2>
|
|
|
<p>以下的命令行参数可以启用指定的 <code>feature</code> :</p>
|
|
|
<ul>
|
|
|
<li><code>--features FEATURES</code>: 启用给出的 feature 列表，可以使用逗号或空格进行分隔，若你是在终端中使用，还需要加上双引号，例如 <code>--features "foo bar"</code>。 若在工作空间中构建多个 <code>package</code>，可以使用 <code>package-name/feature-name</code> 为特定的成员启用 features</li>
|
|
|
<li><code>--all-features</code>: 启用命令行上所选择的所有包的所有 features</li>
|
|
|
<li><code>--no-default-features</code>: 对选择的包禁用 <code>default</code> feature</li>
|
|
|
</ul>
|
|
|
<h2 id="feature-同一化"><a class="header" href="#feature-同一化">feature 同一化</a></h2>
|
|
|
<p><code>feature</code> 只有在定义的包中才是唯一的，不同包之间的 <code>feature</code> 允许同名。因此，在一个包上启用 <code>feature</code> 不会导致另一个包的同名 <code>feature</code> 被误启用。</p>
|
|
|
<p><strong>当一个依赖被多个包所使用时，这些包对该依赖所设置的 <code>feature</code> 将被进行合并，这样才能确保该依赖只有一个拷贝存在，这个过程就被称之为同一化</strong>。大家可以查看<a href="https://doc.rust-lang.org/stable/cargo/reference/resolver.html#features">这里</a>了解下解析器如何对 feature 进行解析处理。</p>
|
|
|
<p>这里，我们使用 <code>winapi</code> 为例来说明这个过程。首先，<code>winapi</code> 使用了大量的 <code>features</code>；然后我们有两个包 <code>foo</code> 和 <code>bar</code> 分别使用了它的两个 features，那么在合并后，最终 <code>winapi</code> 将同时启四个 features :</p>
|
|
|
<img src="https://pic2.zhimg.com/80/v2-251973b0cc83f35cd6858bf21dd00ed6_1440w.png" />
|
|
|
<p>由于这种不可控性，我们需要让 <code>启用feature = 添加特性</code> 这个等式成立，换而言之，<strong>启用一个 feature 不应该导致某个功能被禁止</strong>。这样才能的让多个包启用同一个依赖的不同 features。</p>
|
|
|
<p>例如，如果我们想可选的支持 <code>no_std</code> 环境(不使用标准库)，那么有两种做法：</p>
|
|
|
<ul>
|
|
|
<li>默认代码使用标准库的，当 <code>no_std</code> feature 启用时，禁用相关的标准库代码</li>
|
|
|
<li>默认代码使用非标准库的，当 <code>std</code> feature 启用时，才使用标准库的代码</li>
|
|
|
</ul>
|
|
|
<p>前者就是功能削减，与之相对，后者是功能添加，根据之前的内容，我们应该选择后者的做法：</p>
|
|
|
<pre><pre class="playground"><code class="language-rust edition2021"><span class="boring">#![allow(unused)]
|
|
|
</span>#![no_std]
|
|
|
|
|
|
<span class="boring">fn main() {
|
|
|
</span>#[cfg(feature = "std")]
|
|
|
extern crate std;
|
|
|
|
|
|
#[cfg(feature = "std")]
|
|
|
pub fn function_that_requires_std() {
|
|
|
// ...
|
|
|
}
|
|
|
<span class="boring">}</span></code></pre></pre>
|
|
|
<h4 id="彼此互斥的-feature"><a class="header" href="#彼此互斥的-feature">彼此互斥的 feature</a></h4>
|
|
|
<p>某极少数情况下，features 之间可能会互相不兼容。我们应该避免这种设计，因为如果一旦这么设计了，那你可能需要修改依赖图的很多地方才能避免两个不兼容 feature 的同时启用。</p>
|
|
|
<p>如果实在没有办法，可以考虑增加一个编译错误来让报错更清晰:</p>
|
|
|
<pre><code class="language-toml">#[cfg(all(feature = "foo", feature = "bar"))]
|
|
|
compile_error!("feature \"foo\" and feature \"bar\" cannot be enabled at the same time");
|
|
|
</code></pre>
|
|
|
<p>当同时启用 <code>foo</code> 和 <code>bar</code> 时，编译器就会爆出一个更清晰的错误：feature <code>foo</code> 和 <code>bar</code> 无法同时启用。</p>
|
|
|
<p>总之，我们还是应该在设计上避免这种情况的发生，例如：</p>
|
|
|
<ul>
|
|
|
<li>将某个功能分割到多个包中</li>
|
|
|
<li>当冲突时，设置 feature 优先级，<a href="https://crates.io/crates/cfg-if">cfg-if</a> 包可以帮助我们写出更复杂的 <code>cfg</code> 表达式</li>
|
|
|
</ul>
|
|
|
<h4 id="检视已解析的-features"><a class="header" href="#检视已解析的-features">检视已解析的 features</a></h4>
|
|
|
<p>在复杂的依赖图中，如果想要了解不同的 features 是如何被多个包多启用的，这是相当困难的。好在 <code>cargo tree</code> 命令提供了几个选项可以帮组我们更好的检视哪些 features 被启用了:</p>
|
|
|
<p><code>cargo tree -e features</code> ，该命令以依赖图的方式来展示已启用的 features，包含了每个依赖包所启用的特性：</p>
|
|
|
<pre><code class="language-shell">$ cargo tree -e features
|
|
|
test_cargo v0.1.0 (/Users/sunfei/development/rust/demos/test_cargo)
|
|
|
└── uuid feature "default"
|
|
|
├── uuid v0.8.2
|
|
|
└── uuid feature "std"
|
|
|
└── uuid v0.8.2
|
|
|
</code></pre>
|
|
|
<p><code>cargo tree -f "{p} {f}"</code> 命令会提供一个更加紧凑的视图：</p>
|
|
|
<pre><code class="language-shell">$ cargo tree -f "{p} {f}"
|
|
|
test_cargo v0.1.0 (/Users/sunfei/development/rust/demos/test_cargo)
|
|
|
└── uuid v0.8.2 default,std
|
|
|
</code></pre>
|
|
|
<p><code>cargo tree -e features -i foo</code>，该命令会显示 <code>features</code> 会如何"流入"指定的包 <code>foo</code> 中:</p>
|
|
|
<pre><code class="language-shell">$ cargo tree -e features -i uuid
|
|
|
uuid v0.8.2
|
|
|
├── uuid feature "default"
|
|
|
│ └── test_cargo v0.1.0 (/Users/sunfei/development/rust/demos/test_cargo)
|
|
|
│ └── test_cargo feature "default" (command-line)
|
|
|
└── uuid feature "std"
|
|
|
└── uuid feature "default" (*)
|
|
|
</code></pre>
|
|
|
<p>该命令在依赖图较为复杂时非常有用，使用它可以让你了解某个依赖包上开启了哪些 <code>features</code> 以及其中的原因。</p>
|
|
|
<p>大家可以查看官方的 <code>cargo tree</code> <a href="https://doc.rust-lang.org/stable/cargo/commands/cargo-tree.html">文档</a>获取更加详细的使用信息。</p>
|
|
|
<h2 id="feature-解析器-v2-版本"><a class="header" href="#feature-解析器-v2-版本">Feature 解析器 V2 版本</a></h2>
|
|
|
<p>我们还能通过以下配置指定使用 V2 版本的解析器( <a href="https://doc.rust-lang.org/stable/cargo/reference/resolver.html#resolver-versions">resolver</a> ):</p>
|
|
|
<pre><code class="language-toml">[package]
|
|
|
name = "my-package"
|
|
|
version = "1.0.0"
|
|
|
resolver = "2"
|
|
|
</code></pre>
|
|
|
<p>V2 版本的解析器可以在某些情况下避免 feature 同一化的发生，具体的情况在<a href="https://doc.rust-lang.org/stable/cargo/reference/resolver.html#feature-resolver-version-2">这里</a>有描述，下面做下简单的总结:</p>
|
|
|
<ul>
|
|
|
<li>为特定平台开启的 <code>features</code> 且此时并没有被构建，会被忽略</li>
|
|
|
<li><code>build-dependencies</code> 和 <code>proc-macros</code> 不再跟普通的依赖共享 <code>features</code></li>
|
|
|
<li><code>dev-dependencies</code> 的 <code>features</code> 不会被启用，除非正在构建的对象需要它们(例如测试对象、示例对象等)</li>
|
|
|
</ul>
|
|
|
<p>对于部分场景而言，feature 同一化确实是需要避免的，例如，一个构建依赖开启了 <code>std</code> feature，而同一个依赖又被用于 <code>no_std</code> 环境，很明显，开启 <code>std</code> 将导致错误的发生。</p>
|
|
|
<p>说完优点，我们再来看看 V2 的缺点，其中增加编译构建时间就是其中之一，原因是同一个依赖会被构建多次(每个都拥有不同的 feature 列表)。</p>
|
|
|
<blockquote>
|
|
|
<p>由于此部分内容可能只有极少数的用户需要，因此我们并没有对其进行扩展，如果大家希望了解更多关于 V2 的内容，可以查看<a href="https://doc.rust-lang.org/stable/cargo/reference/features.html#feature-resolver-version-2">官方文档</a></p>
|
|
|
</blockquote>
|
|
|
<h2 id="构建脚本"><a class="header" href="#构建脚本">构建脚本</a></h2>
|
|
|
<p><a href="https://course.rs/cargo/reference/build-script/intro.html">构建脚本</a>可以通过 <code>CARGO_FEATURE_<name></code> 环境变量获取启用的 <code>feature</code> 列表，其中 <code><name></code> 是 feature 的名称，该名称被转换成大全写字母，且 <code>-</code> 被转换为 <code>_</code>。</p>
|
|
|
<h2 id="required-features"><a class="header" href="#required-features">required-features</a></h2>
|
|
|
<p>该字段可以用于禁用特定的 Cargo Target：当某个 feature 没有被启用时，查看<a href="https://course.rs/cargo/reference/cargo-target.html#required-features">这里</a>获取更多信息。</p>
|
|
|
<h2 id="semver-兼容性"><a class="header" href="#semver-兼容性">SemVer 兼容性</a></h2>
|
|
|
<p>启用一个 feature 不应该引入一个不兼容 SemVer 的改变。例如，启用的 feature 不应该改变现有的 API，因为这会给用户造成不兼容的破坏性变更。 如果大家想知道哪些变化是兼容的，可以参见<a href="https://doc.rust-lang.org/stable/cargo/reference/semver.html">官方文档</a>。</p>
|
|
|
<p>总之，在新增/移除 feature 或可选依赖时，你需要小心，因此这些可能会造成向后不兼容性。更多信息参见<a href="https://doc.rust-lang.org/stable/cargo/reference/semver.html#cargo">这里</a>，简单总结如下：</p>
|
|
|
<ul>
|
|
|
<li>在发布 <code>minor</code> 版本时，以下通常是安全的:
|
|
|
<ul>
|
|
|
<li><a href="https://doc.rust-lang.org/stable/cargo/reference/semver.html#cargo-feature-add">新增 feature</a> 或<a href="https://doc.rust-lang.org/stable/cargo/reference/semver.html#cargo-dep-add">可选依赖</a></li>
|
|
|
<li><a href="https://doc.rust-lang.org/stable/cargo/reference/semver.html#cargo-change-dep-feature">修改某个依赖的 features</a></li>
|
|
|
</ul>
|
|
|
</li>
|
|
|
<li>在发布 <code>minor</code> 版本时，以下操作应该避免：
|
|
|
<ul>
|
|
|
<li><a href="https://doc.rust-lang.org/stable/cargo/reference/semver.html#cargo-feature-remove">移除 feature</a> 或<a href="https://doc.rust-lang.org/stable/cargo/reference/semver.html#cargo-remove-opt-dep">可选依赖</a></li>
|
|
|
<li><a href="https://doc.rust-lang.org/stable/cargo/reference/semver.html#cargo-remove-opt-dep">将现有的公有代码放在某个 feature 之后</a></li>
|
|
|
<li><a href="https://doc.rust-lang.org/stable/cargo/reference/semver.html#cargo-feature-remove-another">从 feature 列表中移除一个 feature</a></li>
|
|
|
</ul>
|
|
|
</li>
|
|
|
</ul>
|
|
|
<h2 id="feature-文档和发现"><a class="header" href="#feature-文档和发现">feature 文档和发现</a></h2>
|
|
|
<p>将你的项目支持的 feature 信息写入到文档中是非常好的选择:</p>
|
|
|
<ul>
|
|
|
<li>我们可以通过在 <code>lib.rs</code> 的顶部添加<a href="https://course.rs/basic/comment.html#%E6%96%87%E6%A1%A3%E6%B3%A8%E9%87%8A">文档注释</a>的方式来实现。例如 <code>regex</code> 就是<a href="https://github.com/rust-lang/regex/blob/1.4.2/src/lib.rs#L488-L583">这么做的</a>。</li>
|
|
|
<li>若项目拥有一个用户手册，那也可以在那里添加说明，例如 <a href="https://github.com/rust-lang/regex/blob/1.4.2/src/lib.rs#L488-L583">serde.rs</a>。</li>
|
|
|
<li>若项目是二进制类型(可运行的应用服务，包含 <code>fn main</code> 入口)，可以将说明放在 <code>README</code> 文件或其他文档中，例如 <a href="https://github.com/mozilla/sccache/blob/0.2.13/README.md#build-requirements">sccache</a>。</li>
|
|
|
</ul>
|
|
|
<p>特别是对于不稳定的或者不该再被使用的 feature 而言，它们更应该被放在文档中进行清晰的说明。</p>
|
|
|
<p>当构建发布到 <code>docs.rs</code> 上的文档时，会使用 <code>Cargo.toml</code> 中的元数据来控制哪些 features 会被启用。查看 <a href="https://docs.rs/about/metadata">docs.rs 文档</a>获取更多信息。</p>
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<p>当依赖库的文档没有相关信息时，你也可以通过源码仓库的 <code>Cargo.toml</code> 文件来获取，但是有些时候，使用这种方式来跟踪并获取全部相关的信息是相当困难的。</p>
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