[RUST]Concurrency 1.0 (#3)

concurrency-getting-started.rs

use std::thread;
use std::time::Duration;
// this simple example spwans a thread and runs an operation while running the same operation on the main thread

fn main() {
    // the thread::spawn function expects a Closure; Rust closure syntax is |params_list...| { expr body }
    // if the exprsesion is one line curly braces can be omitted
    // type annotations are optional in closures, as Rust implicitly infers the types the first time the Closure is called
    let handle = thread::spawn(|| {
        for i in 1..10 {
            println!("hi number {} from the spawned thread!", i);
            thread::sleep(Duration::from_millis(1));
        }
    });
    
    for i in 1..5 {
        println!("hi number {} from the main thread!", i);
        thread::sleep(Duration::from_millis(1));
    }
    
    // without this line, the first loop won't finish!
    handle.join().unwrap();

}