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