thread_handles.rs

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

let handles: Vec<_> = (0..100)
    .map(|num| {
        thread::spawn(move || {
            thread::sleep(Duration::from_secs(1));
            println!("value of {}", num);
        })
    })
    .collect();

for handle in handles {
    handle.join().unwrap();
}