src/test/ui/issues/issue-18783.rs

   1 use std::cell::RefCell;
   2
   3 fn main() {
   4     let mut y = 1;
   5     let c = RefCell::new(vec![]);
   6     c.push(Box::new(|| y = 0));
   7     c.push(Box::new(|| y = 0));
   8 //~^ ERROR cannot borrow `y` as mutable more than once at a time
   9 }
  10
  11 fn ufcs() {
  12     let mut y = 1;
  13     let c = RefCell::new(vec![]);
  14
  15     Push::push(&c, Box::new(|| y = 0));
  16     Push::push(&c, Box::new(|| y = 0));
  17 //~^ ERROR cannot borrow `y` as mutable more than once at a time
  18 }
  19
  20 trait Push<'c> {
  21     fn push<'f: 'c>(&self, push: Box<dyn FnMut() + 'f>);
  22 }
  23
  24 impl<'c> Push<'c> for RefCell<Vec<Box<dyn FnMut() + 'c>>> {
  25     fn push<'f: 'c>(&self, fun: Box<dyn FnMut() + 'f>) {
  26         self.borrow_mut().push(fun)
  27     }
  28 }