簡介

元組可以由多種類型組成，長度固定。

創建元組

// 固定類型
let tup1: (i32, f64, u8) = (500, 8.8, 1);// 不固定類型
let tup2 = (500.99, 8.8, 1, 9.99);println!("{}", tup2.0);

用模式匹配解構元組

let tup = (500.99, 8.8, 1, 9.99);
let (x, y, z, e) = tup;
println!("{} {} {} {}", x, y, z, e);

訪問元組

通過 .索引 訪問。

println!("{}", tup2.0);

元組作為函數返回值

fn main() {let s = String::from("hello");let (s2, len) = calc_str_len(s);println!("{} {}", s2, len);
}fn calc_str_len(s: String) -> (String, usize) {let len = s.len();(s, len)
}

元組太長，無法輸出

fn main() {let too_long_tuple = (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13);println!("too long tuple: {:?}", too_long_tuple); // ERROR
}

fn main() {let too_long_tuple = (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12);println!("too long tuple: {:?}", too_long_tuple); // SUCCESS
}

https://fanjuanddz.com/article/43