How to map atomic values in array in Rust-CodePudding

I want to write a program with 2 threads. The first one should update data and the second one should use it. The problem is both of the threads must use the same data. As I understand I can't use mutex in this case. I tried to write a program using static and I did it well. But using static is unsafe, so I decided to found a safe solution.

As I understand in my case it's better to use atomic values. So, I've created an array of atomic values. And the code is not working now, and I can't understand why

use std::{thread, time::{Duration}, sync::{Arc, atomic::{AtomicU16, Ordering}}};
use rdev::{Key, EventType};

fn main()  {
    let data = Arc::new([0_u16; 6].map(|it| AtomicU16::new(it)));
    write(Arc::clone(&data));
    listen(data);
}

fn write(data: Arc<[AtomicU16; 6]>) {
    thread::spawn(move || {
        loop {
            let row = data.map(|it| it.load(Ordering::Relaxed).to_string()).join(";");
//                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
//                    |
//                    cannot move out of here
//                    move occurs because value has type `[AtomicU16; 6]`, which does not implement the `Copy` trait

            println!("{row}");
            thread::sleep(Duration::from_secs(1));
        }
    });
}

Could you please explain me, how can I map these values?

CodePudding user response：

Do not use map directly, which consumes the array, use an iterator instead (which yields references to the inner values), then map over the iterator:

use std::{
    sync::{
        atomic::{AtomicU16, Ordering},
        Arc,
    },
    thread,
    time::Duration,
};

fn main() {
    let data = Arc::new([0_u16; 6].map(|it| AtomicU16::new(it)));
    write(Arc::clone(&data));
}

fn write(data: Arc<[AtomicU16; 6]>) {
    thread::spawn(move || loop {
        let row = data
            .iter()
            .map(|it| it.load(Ordering::Relaxed).to_string())
            .collect::<Vec<String>>()
            .join(";");

        println!("{row}");
        thread::sleep(Duration::from_secs(1));
    });
}

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