mutable_borrow
fn main() { let mut x = String::from("Hello"); world(&mut x); println!("{}", x) } fn world(s : &mut String) { s.push_str(", world") }
fn main() { let mut x = String::from("Hello"); world(&mut x); println!("{}", x) } fn world(s : &mut String) { s.push_str(", world") }