Rust - 数据类型

基础类型有

• integer
• float
• boolean
• char

0x01 integer

• 类型定义

   // 分为有符号 和 无符号整形 
    let a1: i8;
    let a2: i16;
    let a3: i32;
    let a4: i64;
    let a5: i128;
    let a6: isize;
    let b1: u8;
    let b2: u16;
    let b3: u32;
    let b4: u64;
    let b5: u128;
    let b6: usize;

• 值定义

包含了八进制和二进制的值定义, 这个可以赞一下

    let c1 = 19_80; // 10
    let c2 = 0xff;  // 16
    let c3 = 0o77;  // 8
    let c4 = 0b0001_0001; // 2
    let c5 = b'A'; // byte

0x02 float

    let f1: f32 = 2.0;
    let f2: f64 = 3.0;

0x03 bool

    let g1 = true;
    let g2: bool = false;

0x04 char

    let h = 'z';
    let h2 = 'Z';

组合类型

0x05 tuple

    let tup: (i32, f32, u8, bool) = (500, 6.4, 1, true);
    let (x, y, z, b) = tup;

0x06 array

每一个元素必需使用相同的类型

    let arr = [1, 2, 3, 4, 5];
    let weekdays: [&str; 3] = ["mon", "tue", "wedn"];
    let blankArr = [3; 5]; // = let blankArr = [3,3,3,3,3]

    let ele1 = arr[0];
    let ele2 = arr[1];

• array 的两个遍历方法

    let s = String::from("hello");
    let x = s.as_bytes();

    for (i, &item) in x.iter().enumerate() {
        println!("{} - {}", i, item);
    }
    
    println!("{}", "-------");

    for t in x.iter() {
        println!("{}", t);
    }