常见概念

  1. //常量
  2. const MAX: u32 = 100_000;
  4. fn main() {
  5.     //不可变
  6.     let x = 5;
  7.     //可变
  8.     let mut v = 6;
  9.     v = 7
  10. }

隐藏（Shadowing）

可以作为变量名服用

  1. fn main() { 
  2.     let x = 5;
  3.     let x = x + 1;
  4.     let x = x + 2;
  5.     println!("{}", x);
  6. }

数据类型

  1. fn main() {
  2.     let guess: u32 = "42".parse();
  3.     let foo  = 98_222;
  4.     // 四字节Unicode
  5.     let c = 'z';
  6.     // 元组与解构
  7.     let tup = (6.4, 1, 't');
  8.     let (x, y, z) = tup;
  9.     let a = [1, 2, 4];
  10. }

函数

  1. fn main() {
  2.     let x = foo();
  3. }
  4. fn foo() -> i32 {
  5.     5
  6. }

控制流

  1. fn main() {
  2.     let mut x = 5;
  3.     let num = if x > 5 {
  4.         5
  5.     } else {
  6.         6
  7.     };
  8.     println!("{}", num);
  9.     let r = loop {
  10.         x += 1;
  11.         if x == 10 {
  12.             break x;
  13.         }
  14.     };
  15.     println!("{}", r);
  17. }
  1. fn main() {
  2.     let a = [1, 2, 4];
  3.     for x in a.iter() {
  4.         println!("{}", x)
  5.     }
  7.     for x in (1..4).rev() {
  8.         println!("{}", x)
  9.     }
  11. }

结构体

元组结构体

  1. struct Color(i32, i32, i32);

结构体方法

  1. struct Rectangle {
  2.     width: u32,
  3.     height: u32,
  4. }
  6. impl Rectangle {
  7.     fn area(&self) -> u32 {
  8.         self.width * self.height
  9.     }
  10. }
  12. fn main() {
  13.     let rect = Rectangle { width: 3, height: 4};
  14.     println!("{}", rect.area());
  15. }

资料

https://github.com/rust-lang-cn/rust-by-example-cn