31 lines
451 B
Rust
31 lines
451 B
Rust
#![allow(non_camel_case_types)]
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use std::cell::Cell;
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struct dtor<'a> {
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x: &'a Cell<isize>,
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}
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impl<'a> Drop for dtor<'a> {
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fn drop(&mut self) {
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self.x.set(self.x.get() - 1);
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}
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}
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fn unwrap<T>(o: Option<T>) -> T {
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match o {
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Some(v) => v,
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None => panic!()
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}
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}
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pub fn main() {
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let x = &Cell::new(1);
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{
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let b = Some(dtor { x:x });
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let _c = unwrap(b);
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}
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assert_eq!(x.get(), 0);
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}
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