环境
- Rust 1.56.1
- VSCode 1.61.2
概念
参考:https://doc.rust-lang.org/stable/rust-by-example/flow_control/match/binding.html
示例
绑定到变量
fn age() -> u32 {
15
}
fn main() {
match age() {
0 => println!("I haven't celebrated my first birthday yet"),
// 如果要使用变量,则需要绑定到变量
n @ 1..=12 => println!("I'm a child of age {:?}", n),
n @ 13..=19 => println!("I'm a teen of age {:?}", n),
n => println!("I'm an old person of age {:?}", n),
}
}
绑定到枚举
fn some_number() -> Option<u32> {
Some(42)
}
fn main() {
match some_number() {
// 枚举的解构绑定
Some(n @ 42) => println!("The Answer: {}!", n),
Some(n) => println!("Not interesting... {}", n),
_ => (),
}
}
总结
了解了 Rust 中的匹配绑定,在匹配的过程中,如果没有直接变量,可以使用变量绑定。