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use std::cell::RefCell;
fn main() {
let mut y = 1;
let c = RefCell::new(vec![]);
c.push(Box::new(|| y = 0));
c.push(Box::new(|| y = 0));
//~^ ERROR cannot borrow `y` as mutable more than once at a time
}
fn ufcs() {
let mut y = 1;
let c = RefCell::new(vec![]);
Push::push(&c, Box::new(|| y = 0));
Push::push(&c, Box::new(|| y = 0));
//~^ ERROR cannot borrow `y` as mutable more than once at a time
}
trait Push<'c> {
fn push<'f: 'c>(&self, push: Box<dyn FnMut() + 'f>);
}
impl<'c> Push<'c> for RefCell<Vec<Box<dyn FnMut() + 'c>>> {
fn push<'f: 'c>(&self, fun: Box<dyn FnMut() + 'f>) {
self.borrow_mut().push(fun)
}
}
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