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- [3.2 基本数据类型](./chapter_3/chapter_3_2.md) + - [3.3 函数](./chapter_3/chapter_3_3.md) + - [3.4 注释](./chapter_3/chapter_3_4.md) + - [3.5 控制流](./chapter_3/chapter_3_5.md) + - [3.6 Rust内存模型](./chapter_3/chapter_3_6.md) + - [3.7 所有权](./chapter_3/chapter_3_7.md) + - [3.7.1 所有权介绍](./chapter_3/chapter_3_7_1.md) + - [3.7.2 引用与借用](./chapter_3/chapter_3_7_2.md) + - [3.7.3 Slice类型](./chapter_3/chapter_3_7_3.md) +- [4 Rust使用技巧]() diff --git a/assets/1.png b/src/assets/1.png similarity index 100% rename from assets/1.png rename to src/assets/1.png diff --git a/assets/10.png b/src/assets/10.png similarity index 100% rename from assets/10.png rename to src/assets/10.png diff --git a/assets/11.png b/src/assets/11.png similarity index 100% rename from assets/11.png rename to src/assets/11.png diff --git a/assets/12.png b/src/assets/12.png similarity index 100% rename from assets/12.png rename to src/assets/12.png diff --git a/assets/13.png b/src/assets/13.png similarity index 100% rename from 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similarity index 100% rename from assets/8.png rename to src/assets/8.png diff --git a/assets/9.png b/src/assets/9.png similarity index 100% rename from assets/9.png rename to src/assets/9.png diff --git a/src/chapter_2.md b/src/chapter_2.md index 237ce3e..ce787eb 100644 --- a/src/chapter_2.md +++ b/src/chapter_2.md @@ -1,5 +1,5 @@ # 2 欢迎来到Rust的世界 -## 2.1 为什么选择Rust +## 2.1 为什么选择Rust ### 2.1.1 Rust的历史与背景 Rust是一种现代的系统编程语言，它注重性能、安全性和并发。Rust最初由Mozilla研究院的Graydon Hoare于2006年开始设计，最早的目标是为了解决C++在系统编程领域的一些痛点。在2010年，Mozilla正式开始支持这个项目，从那时起，Rust开始迅速发展并逐渐成为一个强大的编程语言。 @@ -17,7 +17,7 @@ Rust的设计理念是将系统编程的性能与安全性相结合。它的核 - 2015年：Rust 1.0正式发布，稳定版本的Rust开始对外提供支持。 - 2016年：Rust开始获得广泛关注，社区逐渐壮大。 - 2018年：WebAssembly的推广使得Rust成为一个受欢迎的前端编程语言。 - + 3. 社区与生态系统 随着Rust的发展，其社区和生态系统也在不断壮大。Rust编程语言被广泛应用于各种领域，如网络编程、游戏开发、操作系统、嵌入式系统、区块链等。此外，Rust已经连续多年被Stack Overflow开发者调查评为最受欢迎的编程语言。 @@ -114,7 +114,8 @@ Rust在系统工具和实用程序开发中也表现出色。Rust编写的工具 1. 对于macOS和Linux用户 通过如下命令进行安装： -``` + +```bash curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh ``` @@ -131,7 +132,8 @@ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh ### 2.2.2 验证安装 安装完成后，可以输入如下命令验证安装： -``` + +```bash rustc --version ``` @@ -140,12 +142,14 @@ rustc --version ### 2.3.1 创建一个新的Rust项目 Rust使用Cargo作为官方的构建工具和包管理器，下面通过Cargo创建一个新的Rust项目： -``` + +```bash cargo new hello_world ``` + 创建后，可以看到整个目录的结构如下： -![目录结构](../assets/62.png) +![目录结构](./assets/62.png) 其中Cargo.toml是项目的配置文件，src为源代码目录，main.rs为主程序文件。 @@ -162,13 +166,13 @@ fn main() { ### 2.3.3 编译并运行Hello, World程序 运行程序需要进去到项目目录中，然后运行cargo run命令即可，步骤如下： -``` +```bash cd hello_world cargo run ``` 运行结果如下： -![运行结果](../assets/63.png) +![运行结果](./assets/63.png) ### 2.3.4 理解Rust源码的基本结构 下面简单介绍Rust源码的结构。 diff --git a/src/chapter_3/chapter_3_2.md b/src/chapter_3/chapter_3_2.md index d6fed86..49c0d51 100644 --- a/src/chapter_3/chapter_3_2.md +++ b/src/chapter_3/chapter_3_2.md @@ -1,4 +1,4 @@ -## 3.2 基本数据类型(Basic Data Type) +## 3.2 基本数据类型 Rust是静态类型语言，编译时就必须知道所有变量的类型。根据值以及其使用方式，Rust编译器通常能自动推导出变量的类型。 Rust有两种数据类型子集，分别是：标量（scalar）类型和复合（compound）类型。 @@ -76,7 +76,7 @@ Rust中的布尔型用bool表示，有两个可能的值，为true和false。布 fn main() { // 定义方式 let a: bool = true; - let b: bool = false; + let b: bool = false; // 使用场景 if a { diff --git a/src/chapter_3/chapter_3_3.md b/src/chapter_3/chapter_3_3.md index f8a560c..be35dc2 100644 --- a/src/chapter_3/chapter_3_3.md +++ b/src/chapter_3/chapter_3_3.md @@ -1,4 +1,5 @@ -## 3.3 函数(Function) +## 3.3 函数 + ### 3.3.1. 函数定义 fn关键字、函数名、函数参数名及其类型（如果有的话）、返回值类型（如果有的话）组成函数签名， 加上由一对花括号包含的函数体组成函数。例子如下： ```Rust diff --git a/src/chapter_3/chapter_3_4.md b/src/chapter_3/chapter_3_4.md index d032ccc..7d30084 100644 --- a/src/chapter_3/chapter_3_4.md +++ b/src/chapter_3/chapter_3_4.md @@ -94,4 +94,4 @@ fn main() { cargo doc --open ``` 将打开上面代码里面文档注释生成的文档，如下图： -![注释](../../assets/1.png) +![注释](../assets/1.png) diff --git a/src/chapter_3/chapter_3_5.md b/src/chapter_3/chapter_3_5.md index 2b0694e..55f5bfe 100644 --- a/src/chapter_3/chapter_3_5.md +++ b/src/chapter_3/chapter_3_5.md @@ -1,4 +1,4 @@ -## 3.5 控制流(Control Flow) +## 3.5 控制流 Rust中的控制流结构主要包括： diff --git a/src/chapter_3/chapter_3_6.md b/src/chapter_3/chapter_3_6.md index b0b6318..b1be7dd 100644 --- a/src/chapter_3/chapter_3_6.md +++ b/src/chapter_3/chapter_3_6.md @@ -1,6 +1,6 @@ ## 3.6 Rust内存模型 ### 3.6.1 Rust程序内存布局 -![注释](../../assets/2.png) +![注释](../assets/2.png) 上图是一张linux系统上Rust程序的内存布局图。在linux操作系统中，会划分固定的区域给内核使用，即上图中的内核空间；应用程序使用的是用户空间。 @@ -38,7 +38,7 @@ fn main() { } ``` 对于上面的代码，在执行第17行和第18行的栈帧示意图如下： -![注释](../../assets/3.png) +![注释](../assets/3.png) 这里需要注意的是两个帧对应同样的内存地址，这是因为在调用完f1函数后，其对应的栈帧释放（释放的实际意义就是这段内存可以被重新分配了），然后调用f2函数为其分配栈帧时从同样的地址进行分配。 @@ -51,4 +51,4 @@ Rust没有GC，但通过其独特的机制管理内存，程序员不用手动 栈中存储的所有数据都必须占用（在编译时就）已知且固定的大小。编译时大小未知或可能变化的数据，存储在堆上。 数据存放到栈上时，是直接将数据放到栈内存。 当数据需要存放到堆上时，内存分配器则是根据数据的大小，在堆内存找到合适大小的空区域存放，把它标记为已使用，并返回一个表示该位置地址的指针。该指针存储在栈上，当需要访问具体的数据时，必须先访问指针，然后通过指针找到堆上的位置，从而访问数据。这个过程可以用下图表示： -![注释](../../assets/4.png) +![注释](../assets/4.png) diff --git a/src/chapter_3/chapter_3_7.md b/src/chapter_3/chapter_3_7.md index 2c387cf..fac4e33 100644 --- a/src/chapter_3/chapter_3_7.md +++ b/src/chapter_3/chapter_3_7.md @@ -1,4 +1,5 @@ -## 3.7.所有权(Ownership) +## 3.7.所有权 + - [所有权介绍](./chapter_3_7_1.md) - [引用与借用](./chapter_3_7_2.md) - [slice类型](./chapter_3_7_3.md) diff --git a/src/chapter_3/chapter_3_7_1.md b/src/chapter_3/chapter_3_7_1.md index 8bf6684..1a698d7 100644 --- a/src/chapter_3/chapter_3_7_1.md +++ b/src/chapter_3/chapter_3_7_1.md @@ -26,12 +26,12 @@ fn main() { ```Rust fn f() { let b = 1u32; // --------------------------------| - let c = 2u32; //-----------| | + let c = 2u32; //-----------| | // | | // | |---b的作用域范围 println!("b = {:?}", b);// |--c的作用与范围 | println!("c = {:?}", c);// | | - //-----------| -------------------| + //-----------| -------------------| } fn main() { @@ -95,7 +95,7 @@ pub struct String { Vec类型的定义如下： ```Rust pub struct Vec { - buf: RawVec, + buf: RawVec, len: usize, // 长度 } ``` @@ -118,7 +118,7 @@ struct String { 更进一步的简化，可以得到String类型本质如下： ```Rust struct String { - ptr：NonNull, + ptr：NonNull, cap: usize， len: usize, } @@ -139,7 +139,7 @@ fn main() { ``` 在第2行定义String类型时，并不能确定最终字符串的大小，所以字符串内容本身应该存储在堆上。结合什么String类型的本质的内容，可以得到String类型的存储如下： -![注释](../../assets/5.png) +![注释](../assets/5.png) String类型本身是三个字段（指针、长度、容量），在编译时是已知的大小，存储在栈上；String类型绑定的字符串（在上面代码中是“AB”）在编译时大小未知，是运行时在堆上分配内存，分配后的内存地址保存在String类型的指针字段中，内存大小保存在cap字段中，内存上存储的字符串长度保存在len字段中。 @@ -171,11 +171,11 @@ fn main() { ``` s是String类型，字符串“Hello world！”是存储在堆内存上的，其内存布局如下： -![注释](../../assets/6.png) +![注释](../assets/6.png) 当执行let s1 = s后，内存布局如下： -![注释](../../assets/7.png) +![注释](../assets/7.png) 当let s1 = s执行后，就发生了所有权的转移，String类型值的所有权从s转移到了s1。此时Rust认为原来的s不再有效。因此，上面代码第4行打开编译将会出错。 @@ -185,14 +185,14 @@ s是String类型，字符串“Hello world！”是存储在堆内存上的， 只拷贝栈上的内容，就叫做浅拷贝。 对于上面的String类型，执行let s1 = s后，只把s的ptr、len、cap中的值拷贝给s1的ptr、len、cap的值，这种就叫做浅拷贝。浅拷贝发生后，s的ptr和s1的ptr都指向同样的堆内存。内存布局如下： -![注释](../../assets/8.png) +![注释](../assets/8.png) - 深拷贝 除了拷贝栈上的内容外，还拷贝堆内存中的内容，就叫做深拷贝。 对于上面的String类型，执行let s1 = s后，除了把s的len、cap中的值拷贝给s1的len、cap外，还在堆上重新分配一块内存，将s的ptr指向的堆内存的内容拷贝到这块内存，然后s1的ptr指向这块内存，这种拷贝就叫做深拷贝。深拷贝发生后，s的ptr和s1的ptr指向不同的堆内存，但是堆内存中存储的内容一样。深拷贝发生后的内存布局如下： -![注释](../../assets/9.png) +![注释](../assets/9.png) 显然，**Rust中变量赋值（Rust中叫所有权转移）使用的是浅拷贝**。 @@ -227,11 +227,11 @@ Rust中，默认实现了Copy trait的类型有： ```Rust fn main() { let s = String::from("hello"); - takes_ownership(s); + takes_ownership(s); // println!("s: {:?}", s);//打开编译会报错，因为s的所有权在上一行已经转移到take_ownership函数中了 - let x = 5; - makes_copy(x); + let x = 5; + makes_copy(x); println!("x: {:?}", x);//不会报错，因为上一行将x传到makes_copy函数时会自动拷贝x的值到函数中 } @@ -239,7 +239,7 @@ fn takes_ownership(some_string: String) { println!("{}", some_string); } -fn makes_copy(some_integer: i32) { +fn makes_copy(some_integer: i32) { println!("{}", some_integer); } ``` diff --git a/src/chapter_3/chapter_3_7_2.md b/src/chapter_3/chapter_3_7_2.md index ec2c0ac..64a9652 100644 --- a/src/chapter_3/chapter_3_7_2.md +++ b/src/chapter_3/chapter_3_7_2.md @@ -40,7 +40,7 @@ fn print(s: String) -> String { ``` 上面代码中，变量a、b、c、d的内存布局如下： -![注释](../../assets/10.png) +![注释](../assets/10.png) **获取变量的引用，称之为借用** 。通过借用，允许使用被引用变量绑定的值，同时又没有移动该变量的所有权。前面的示例代码可以变成如下： ```Rust @@ -178,13 +178,13 @@ fn main() { ``` （2）限制二：**同一作用域，可变引用和不可变引用不能同时存在**。如下代码编译错误： -```Rust +```Rust fn main() { let mut s = String::from("hello"); let r1 = &s; // 没问题 let r2 = &s; // 没问题 let r3 = &mut s; // 大问题，同时存在两个s的引用和一个可变引用 - println!("{}, {}", r1, r2); + println!("{}, {}", r1, r2); println!("{}", r3); } ``` @@ -195,7 +195,7 @@ fn main() { let r1 = &s; // 没问题 let r2 = &s; // 没问题 - println!("{} and {}", r1, r2); + println!("{} and {}", r1, r2); // 此位置之后 r1 和 r2 不再使用， 新编译器中： r1和r2离开了其作用域 let r3 = &mut s; // 没问题，因为r1和r2已不存在，没有同时存在对s的引用和可变引用 @@ -240,11 +240,11 @@ int main() ``` 在执行第14行前，其内存布局为： -![注释](../../assets/11.png) +![注释](../assets/11.png) 当执行第14行后，变成如下： -![注释](../../assets/12.png) +![注释](../assets/12.png) 第14行执行后，ptr就变成了一个悬垂指针（或者交悬垂引用），然后在第16行继续使用ptr，则会发生错误。 @@ -264,13 +264,13 @@ fn dangle() -> &String { *思考：为什么下面的代码是正确的* ？ ```Rust fn main() { - let s = no_dangle(); + let s = no_dangle(); println!("s = {:?}", s); } fn no_dangle() -> String { let s = String::from("hello"); - s + s } // 此处s虽然离开了函数这个作用域范围，但是它的所有权是被转移出去了，值并没有释放 ``` @@ -279,4 +279,3 @@ fn no_dangle() -> String { - 在任意给定时间，要么 只能有一个可变引用，要么 只能有多个不可变引用。 - 引用必须总是有效的（不能是悬垂引用）。 - diff --git a/src/chapter_3/chapter_3_7_3.md b/src/chapter_3/chapter_3_7_3.md index eebef7c..11ceb96 100644 --- a/src/chapter_3/chapter_3_7_3.md +++ b/src/chapter_3/chapter_3_7_3.md @@ -18,7 +18,7 @@ fn main(){ let arr_slice1 = &arr[..=1]; println!("{:?}", arr_slice1); // [11,22]; - let arr_slice2 = &mut arr[..=1]; + let arr_slice2 = &mut arr[..=1]; arr_slice2[0] = 1111; println!("{:?}", arr_slice2);// [1111,22]; println!("{:?}", arr);// [1111,22,33,44]; @@ -44,7 +44,7 @@ fn main() { &str和&String的内存布局如下： -![注释](../../assets/13.png) +![注释](../assets/13.png) #### 3. 其它Slice 数组的Slice，如下： @@ -63,4 +63,3 @@ fn main() { println!("b: {:?}", b); } ``` -