通过例子学rust个人精简版5-all

5 类型转换 fn main() { let decimal = 65.4321_f32; let integer = decimal as u8; let character = integer as char; println!("Casting: {} -> {} -> {}", decimal, integer, character); //Casting: 65.4321 -> 65 -> A } 要点1 ： 精度丢失 个人 ： 不是很能理解 #![allow(overflowing_literals)] 的用途 所以这里我删掉了 字面量 fn main() { // 带后缀的字面量，其类型在初始化时已经知道了。 let x = 1u8; let y = 2u32; let z = 3f32; // 无后缀的字面量，其类型取决于如何使用它们。 let i = 1; let f = 1.0; // `size_of_val` 返回一个变量所占的字节数 println!("size of `x` in bytes: {}", std::mem::size_of_val(&x)); println!("size of `y` in bytes: {}", std::mem::size_of_val(&y)); println!("size of `z` in bytes: {}", std::mem::size_of_val(&z)); println!("size of `i` in bytes: {}", std::mem::size_of_val(&i)); println!("size of `f` in bytes: {}", std::mem::size_of_val(&f)); } size of `x` in bytes: 1 size of `y` in bytes: 4 size of `z` in bytes: 4 size of `i` in bytes: 4 size of `f` in bytes: 8 类型推断

之前有提到过，没啥好说的

别名

之前有提到过，没啥好说的