use std::sync::{Mutex};
use std::thread;

struct ThreadSafeStruct {
    w: Mutex<u64>,
}

impl ThreadSafeStruct {
    fn update(&self, val: u64) {
        let mut v = self.w.lock().unwrap();
        *v = val;
    }

    fn get(&self) -> u64 {
        let v = self.w.lock().unwrap();
        *v
    }
}

fn main() {
    let ilivelongenough: ThreadSafeStruct  = ThreadSafeStruct {
        w: Mutex::new(200),
    };

    let ilivelongenough_ref = &ilivelongenough;

    let thread_handle = thread::spawn(move || {

        println!("Value of ilivelongenough in another thread is: {}.", ilivelongenough_ref.get());

        thread::sleep(std::time::Duration::from_secs(1));
    });

    thread_handle.join().unwrap_or_default();

    println!("ilivelongenough in this thread is: {}.", ilivelongenough.get());
}