结构体1: exercises/structs/structs1.rs

题目

rust

// structs1.rs
//
// Address all the TODOs to make the tests pass!
//
// Execute `rustlings hint structs1` or use the `hint` watch subcommand for a
// hint.

// I AM NOT DONE

struct ColorClassicStruct {
    // TODO: Something goes here
}

struct ColorTupleStruct(/* TODO: Something goes here */);

#[derive(Debug)]
struct UnitLikeStruct;

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn classic_c_structs() {
        // TODO: Instantiate a classic c struct!
        // let green =

        assert_eq!(green.red, 0);
        assert_eq!(green.green, 255);
        assert_eq!(green.blue, 0);
    }

    #[test]
    fn tuple_structs() {
        // TODO: Instantiate a tuple struct!
        // let green =

        assert_eq!(green.0, 0);
        assert_eq!(green.1, 255);
        assert_eq!(green.2, 0);
    }

    #[test]
    fn unit_structs() {
        // TODO: Instantiate a unit-like struct!
        // let unit_like_struct =
        let message = format!("{:?}s are fun!", unit_like_struct);

        assert_eq!(message, "UnitLikeStructs are fun!");
    }
}

补充所有TODO的地方，让单元测试通过。

题目解析

先来看第一个单元测试：

rust

#[test]
    fn classic_c_structs() {
        // TODO: Instantiate a classic c struct!
        // let green =

        assert_eq!(green.red, 0);
        assert_eq!(green.green, 255);
        assert_eq!(green.blue, 0);
    }

需要使用ColorClassicStruct结构体，从测试的代码来看应该是具名结构体：

rust

// 结构体定义
struct ColorClassicStruct {
    red: u32,
    green: u32,
    blue: u32,
}

// 创建
let green = ColorClassicStruct {
    red: 0,
    green: 255,
    blue: 0,
};

再来看第二个测试代码：

rust

#[test]
    fn tuple_structs() {
        // TODO: Instantiate a tuple struct!
        // let green =

        assert_eq!(green.0, 0);
        assert_eq!(green.1, 255);
        assert_eq!(green.2, 0);
    }

需要使用ColorTupleStruct结构体，从测试的代码来看应该是元组结构体：

rust

// 结构体定义
struct ColorTupleStruct(u32, u32, u32);

// 创建
let green = ColorTupleStruct(0, 255, 0);

紧接着看第三个测试代码，UnitLikeStruct是单元结构体：

rust

#[test]
    fn unit_structs() {
        // TODO: Instantiate a unit-like struct!
        // let unit_like_struct =
        let message = format!("{:?}s are fun!", unit_like_struct);

        assert_eq!(message, "UnitLikeStructs are fun!");
    }

我们直接创建即可：

rust

let unit_like_struct = UnitLikeStruct {};

最终代码为：

rust

struct ColorClassicStruct {
    // TODO: Something goes here
    red: u32, 
    green: u32, 
    blue: u32, 
}

struct ColorTupleStruct(/* TODO: Something goes here */); 
struct ColorTupleStruct(u32, u32, u32); 

#[derive(Debug)]
struct UnitLikeStruct;

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn classic_c_structs() {
        // TODO: Instantiate a classic c struct!
        // let green =  
        let green = ColorClassicStruct {  
            red: 0, 
            green: 255, 
            blue: 0, 
        }; 

        assert_eq!(green.red, 0);
        assert_eq!(green.green, 255);
        assert_eq!(green.blue, 0);
    }

    #[test]
    fn tuple_structs() {
        // TODO: Instantiate a tuple struct!
        // let green =  
        let green = ColorTupleStruct(0, 255, 0); 

        assert_eq!(green.0, 0);
        assert_eq!(green.1, 255);
        assert_eq!(green.2, 0);
    }

    #[test]
    fn unit_structs() {
        // TODO: Instantiate a unit-like struct!
        // let unit_like_struct =
        let unit_like_struct = UnitLikeStruct {}; 
        let message = format!("{:?}s are fun!", unit_like_struct);

        assert_eq!(message, "UnitLikeStructs are fun!");
    }
}

参考资料

结构体的定义和实例化

结构体1: exercises/structs/structs1.rs ​

题目 ​

题目解析 ​

参考资料 ​

结构体1: exercises/structs/structs1.rs

题目

题目解析

参考资料