error[E0277]: `()` doesn't implement `std::fmt::Display` --> src\main.rs:3:41 | 3 | println!("This will not print: {}", doesnt_print); | ^^^ `()` cannot be formatted with the default formatter | = help: the trait `std::fmt::Display` is not implemented for `()` =...
如果去掉第一行#[derive(Debug)],IDE提示 `Person<'_>` doesn't implement `std::fmt::Debug` `Person<'_>` cannot be formatted using `{:?}` help: the trait `std::fmt::Debug` is not implemented for `Person<'_>` note: add `#[derive(Debug)]` or manually implement `std::fmt::Debug...
println!("{}",xx)报错doesn't implement `std::fmt::Display` println!("{:?}",xx); println!("{:?}",xx);xx带struct报错'Struct` doesn't implement `Debug` #[derive(Debug)] struct xx { } 类似报错 error[E0277]: `impl futures::Future<Output = Result<Vec<Value>, anyhow::Error>>`...
14. 如果去掉第一行#[derive(Debug)],IDE提示 `Person<'_>` doesn't implement `std::fmt::Debug` `Person<'_>` cannot be formatted using `{:?}` help: the trait `std::fmt::Debug` is not implemented for `Person<'_>` note: add `#[derive(Debug)]` or manually implement `std::fmt:...
error[E0277]: `poker::Card` doesn'timplement `std::fmt::Debug` -->src\main.rs:14:22|14|println!("{:?}", card); | ^^^ `poker::Card` cannot be formatted using `{:?}` | = help: thetrait`std::fmt::Debug` is not implementedfor`poker::Card` =...
//错误代码:`Rectangle` doesn't implement `std::fmt::Display`structRectangle{width:u32,height:u32,}fnmain(){letrect1=Rectangle{width:30,height:50,};println!("rect1 is {}",rect1);} println! 宏能处理很多类型的格式,不过,{} 默认告诉 println! 使用被称为 Display 的格式:意在提供给直接终端...
打印结构体(debug display) structRectangle{width:u32,height:u32,}fnmain(){letrect1=Rectangle{width:30,height:50,};println!("rect1 is {}",rect1);// error[E0277]: `Rectangle` doesn't implement `std::fmt::Display`// // {:?} 表示我们使用Debug输出格式println!("rect1 is {:?}",rect...
Print the value of object x having custom type T, for log or debug. 打印自定义类型的值 代码语言:javascript 代码运行次数:0 运行 AI代码解释 package main import ( "fmt" ) // T represents a tank. It doesn't implement fmt.Stringer. type T struct { name string weight int firePower int }...
error[E0277]:`Rectangle`doesn't implement `std::fmt::Debug` --> src/main.rs:6:28 | 6 | println!("rec = {:?}", rectange1); | ^^^ `Rectangle` cannot be formatted using `{:?}` | = help: the trait `std::fmt::Debug` is not implemented for `Rectangle` = note: ...
在本例中,使用宏打印结构体println!("{:?}", s);时,第一行的代码#[derive(Debug)]是必须的,如果去掉就会报错: error[E0277]: `Student` doesn't implement `Debug` --> E:\.rs\struct2.rs:31:22 | 31 | println!("{:?}", s);