source: example/unnecessary-arc.rs@ 06ffa95

use std::thread;
use std::time::Duration;

// This is the version I wished worked.
// If join was't ingored it would be safe
fn better() {
        // let durr = Duration::from_millis(1);
        {
                let thrd = thread::spawn(move || {
                        for i in 1..10 {
                                println!("hi number {} from the spawned thread!", i);
                                thread::sleep(durr);
                        }
                });

                for i in 1..5 {
                        println!("hi number {} from the main thread!", i);
                        thread::sleep(durr);
                }

                thrd.join().unwrap();
        }
}

use std::sync::Arc;

// This uses arc, which should not be needed
// But it fails to figure out where to clone so it doesn't compile
fn best() {
        let durr = Arc::new(Duration::from_millis(1));
        {
                let thrd = thread::spawn(|| {
                        for i in 1..10 {
                                println!("hi number {} from the spawned thread!", i);
                                thread::sleep(*durr);
                        }
                });

                for i in 1..5 {
                        println!("hi number {} from the main thread!", i);
                        thread::sleep(*durr);
                }

                thrd.join().unwrap();
        }
}

// This is what is actually required
// Note that the clone is explicit
fn real() {
        let durr = Arc::new(Duration::from_millis(1));
        {
                let durr2 = durr.clone();
                let thrd = thread::spawn(move || {
                        for i in 1..10 {
                                println!("hi number {} from the spawned thread!", i);
                                thread::sleep(*durr2);
                        }
                });

                for i in 1..5 {
                        println!("hi number {} from the main thread!", i);
                        thread::sleep(*durr);
                }

                thrd.join().unwrap();
        }
}

fn main() {
        best();
        better();
        real();
}