1. In the folder bin, create a file called sharing_in_closures.rs.

2. Add the following code and run it with cargo run --bin sharing_in_closures:

1  use std::thread;
2  use std::sync::Arc;
3  
4  fn main() {
5    // An Arc ("Atomically Reference Counted") is used the exact
6    // same way as an Rc, but also works in a parallel context
7    let some_resource = Arc::new("Hello World".to_string());
8 
9    // We use it to give a new thread ownership of a clone of the 
        Arc
10   let thread_a = {
11     // It is very common to give the clone the same name as the 
          original
12     let some_resource = some_resource.clone();
13     // The clone is then moved into the closure:
14     thread::spawn(move || {
15       println!("Thread A says: {}", some_resource);
16      })
17   };
18   let thread_b = {
19       let some_resource = some_resource.clone();
20       thread::spawn(move || {
21         println!("Thread B says: {}", some_resource);
22        })
23   };
24 
25  // .join() blocks the main thread until the other thread is done
26  thread_a.join().expect("Thread A panicked");
27  thread_b.join().expect("Thread B panicked");
28  }