從 Rust 中的結構實例引用值時的范圍問題

Question

所以我有了這個程序，一切都按照我的意願工作。 唯一的問題是底部的“student1.name”。 我想用“student1.name”替換“self.name”，但我遇到了范圍問題。 “self.name”工作得很好。 這是我的代碼：

 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);
    }
}

這是我的 output：

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.

有任何想法為什么會發生這種情況（我是 Rust 初學者，所以請盡量讓你的解釋簡單）？

Answer 1

特征實現方法與調用它們的 function 完全不同。

如果您希望能夠在調用中使用學生的姓名，則必須向 function 添加一個參數。 例子：

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);
    }
}

現在調用如下：

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