有没有一种简单的方法来格式化和打印枚举值?我以为它们会有一个默认的实现std::fmt::Display
,但是似乎并不是这样。
enum Suit {
Heart,
Diamond,
Spade,
Club
}
fn main() {
let s: Suit = Suit::Heart;
println!("{}", s);
}
期望输出:
错误:error[E0277]: the trait bound `Suit: std::fmt::Display` is not satisfied
--> src/main.rs:10:20
|
10 | println!("{}", s);
| ^ the trait `std::fmt::Display` is not implemented for `Suit`
|
= note: `Suit` cannot be formatted with the default formatter; try using `:?` instead if you are using a format string
= note: required by `std::fmt::Display::fmt`