从 Rust 中的结构实例引用值时的范围问题

Question

所以我有了这个程序，一切都按照我想要的方式工作。唯一的问题是底部的“student1.name”。我想用“student1.name”替换“self.name”，但我遇到了范围界定问题。 “self.name”工作得很好。这是我的代码：

 fn main() {
    let student1 = IOT_student {
        name: String::from("Husayn Abbas"),
        age: 13,
        education: String::from("O Levels"),
    };

    let instructor1 = IOT_instructor {
        name: String::from("Imran Ali"),
        age: 25,
    };

    println!("{}", student1.ask_Questions());
    println!("{}", instructor1.ask_Questions());
}

trait Questions {
    fn ask_Questions(&self) -> String;
}

struct IOT_student {
    name: String,
    age: i8,
    education: String,
}

struct IOT_instructor {
    name: String,
    age: i8,
}

impl Questions for IOT_student {
    fn ask_Questions(&self) -> String {
        return format!("Zoom session will be LIVE, Zoom recording will not be available. Quarter 2 studio recorded videos are available on Portal.");
    }
}

impl Questions for IOT_instructor {
    fn ask_Questions(&self) -> String {
        return format!("{} In case of any issue email to education@piaic.org", student1::name);
    }
}

这是我的输出：

Compiling IOT_Assignment_2 v0.1.0 (/home/memelord/Documents/PIAIC Quarter 2 IOT Assignments/IOT_Assignment_2)
error[E0425]: cannot find value `student1` in this scope
  --> src/main.rs:40:80
   |
40 |         return format!("{} In case of any issue email to education@piaic.org", student1.name);
   |                                                                                ^^^^^^^^ not found in this scope

warning: type `IOT_student` should have an upper camel case name
  --> src/main.rs:21:8
   |
21 | struct IOT_student {
   |        ^^^^^^^^^^^ help: convert the identifier to upper camel case: `IotStudent`
   |
   = note: `#[warn(non_camel_case_types)]` on by default

warning: type `IOT_instructor` should have an upper camel case name
  --> src/main.rs:27:8
   |
27 | struct IOT_instructor {
   |        ^^^^^^^^^^^^^^ help: convert the identifier to upper camel case: `IotInstructor`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0425`.
error: could not compile `IOT_Assignment_2`.

To learn more, run the command again with --verbose.

知道为什么会这样（我是 Rust 初学者，所以请尽量让您的解释简单明了）？

Answer 1

特征实现方法与调用它们的函数完全不同。

如果您希望能够在调用中使用学生的姓名，则必须向该函数添加一个参数。示例：

impl Questions for IOT_instructor {
    fn ask_Questions(&self, student: &IOT_student) -> String {
        return format!("{} In case of any issue email to education@piaic.org", student.name);
    }
}

现在像这样打电话：

println!("{}", instructor1.ask_Questions(&student1));

从 Rust 中的结构实例引用值时的范围问题

Scoping Issues when referring value from Struct Instance in Rust

rust

rust-cargo