|
use std::cell::RefCell;
|
|
|
|
|
|
|
|
fn main() {
|
|
let m = RefCell::new(0);
|
|
let mut b = m.borrow_mut();
|
|
let b1 = &mut *b;
|
|
let b2 = &mut *b; //~ ERROR cannot borrow
|
|
b1.use_mut();
|
|
}
|
|
|
|
trait Fake { fn use_mut(&mut self) { } fn use_ref(&self) { } }
|
|
impl<T> Fake for T { }
|