Shared via Rust Playground

playground.rs

use std::mem::{replace};

#[derive(Clone, Debug)]
struct HasDrop(i32);

impl Drop for HasDrop {
    fn drop(&mut self) {
        println!("Dropping {}!", self.0);
    }
}

fn bye<T>(_: T) {}

fn kill_and_get<T>(mut v : Vec<T>, i: usize) -> T {
    v.swap_remove(i)
}

fn main() {
    let mut z = Box::new([1; 20]);
    let z2 = z.clone();
    z[10] = 5;
    println!("{}",z2[10] + z[10]);
    
    let x = vec![HasDrop(1), HasDrop(2)];
    let str = {format!("{:?}",x.get(1).cloned())};
    println!("{}",str);
    println!("a");
    let y = kill_and_get(x, 1);
    println!("c");
    bye(y);
    println!("d");
    let mut _a = vec![HasDrop(3),HasDrop(4)];
    replace(&mut _a[1],HasDrop(5));
}