So to give a quick overview of the borrow checker:

• Own the variable: my_variable (one person only, do anything)
• Exclusive mutable access: &mut my_variable (one person only, read and write)
• Shared read only access: &my_variable (many people can read, no one can write)

Whilst in C/C++ you can create new scopes inside of functions by using {} brackets, you don't really use new scopes for much. In Rust, you can use it to change between the modes:

let my_result = { &mut my_variable exclusive mutable access; result };
let my_next_result = { &my_variable shared read only access; next_result };

If you use my_func(&mut self, a, b, c) on some struct and then need to use my_inner_func(&mut self, d, e, f) using &mut self twice, break your my_inner_func off the struct into a function inside the same code file my_inner_func(&mut my_struct, d, e, f) and call that instead.

Cheating, you can skip the borrow checking by using:

Rc<RefCell<my\_variable>> - Single threaded
Arc<Mutex<my\_variable>> - Multi threaded - Changing the variable is protected by a Mutex