附录 A Rust 速查表

目录

附录 A Rust 速查表#

        mindmap
  root((Rust 速查))
    基础语法
      let
      fn
      match
    所有权
      T
      ref
      mut ref
    错误处理
      Option
      Result
      question mark
    工程常用
      serde
      tokio
      sqlx

基础语法#

let name = String::from("Hive");
let count: u32 = 3;
let enabled = true;

fn add(a: i32, b: i32) -> i32 {
    a + b
}

所有权与借用#

写法	含义
`T`	拥有值
`&T`	不可变借用
`&mut T`	可变借用
`Clone`	显式复制堆上数据
`Copy`	按位复制，原值仍可用

fn print_title(title: &str) {
    println!("{title}");
}

fn rename(title: &mut String) {
    title.push_str(" v2");
}

Option 与 Result#

let value: Option<String> = Some("hello".into());
let text = value.unwrap_or_else(|| "default".into());

fn read_config() -> Result<String, std::io::Error> {
    std::fs::read_to_string("config.toml")
}

struct / enum / match#

struct Note {
    id: String,
    title: String,
}

enum Command {
    Create(Note),
    Delete(String),
}

match command {
    Command::Create(note) => println!("{}", note.title),
    Command::Delete(id) => println!("delete {id}"),
}

Trait 与泛型#

trait Repository<T> {
    fn save(&self, value: T) -> anyhow::Result<()>;
}

fn persist<T, R>(repo: &R, value: T) -> anyhow::Result<()>
where
    R: Repository<T>,
{
    repo.save(value)
}

async / await#

async fn fetch(url: &str) -> anyhow::Result<String> {
    let body = reqwest::get(url).await?.text().await?;
    Ok(body)
}

常用 crate#

crate	用途
`serde`	序列化 / 反序列化
`thiserror`	定义错误类型
`anyhow`	应用层错误聚合
`tokio`	异步运行时
`reqwest`	HTTP 客户端
`sqlx`	异步 SQL
`tracing`	结构化日志