rust - 如何访问数组类型结构的元素

Question

我创建了以下结构

pub const BUCKET_SIZE: usize = 4;

pub const FINGERPRINT_SIZE: usize = 1;

pub struct Fingerprint ([u8; FINGERPRINT_SIZE]);

impl Fingerprint {
    pub fn new(bytes: [u8; FINGERPRINT_SIZE]) -> Fingerprint {
        return Fingerprint(bytes);
    }
}

pub struct Bucket ([Fingerprint; BUCKET_SIZE]);

impl Bucket {
    pub fn new(fingerprints: [Fingerprint; BUCKET_SIZE]) -> Bucket {
        Bucket(fingerprints)
    }
    pub fn insert(&self, fp: Fingerprint) -> bool {
        for i in 0..BUCKET_SIZE {



            //HERE IS THE ERROR
            if (self[i as usize] == 0) {
                self[i as usize] = fp;
                return true;
            }



        }
        return false;
    }
}

尝试编译时出现以下错误

error: cannot index a value of type `&bucket::Bucket`

让 Buckets 保存属性指纹是否更有意义？

Answer 1

Bucket 类型是一个具有一个字段的元组结构，您可以使用 .0 访问它。

因此您可以将代码更改为:

        if (self.0[i as usize] == 0) {
            self.0[i as usize] = fp;
            return true;
        }

您还需要将函数参数从 &self 更改为 &mut self 以便您可以改变 self 的字段。