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32 lines
658 B
Rust
32 lines
658 B
Rust
//@ run-pass
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#![allow(non_camel_case_types)]
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use std::cell::Cell;
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struct shrinky_pointer<'a> {
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i: &'a Cell<isize>,
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}
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impl<'a> Drop for shrinky_pointer<'a> {
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fn drop(&mut self) {
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println!("Hello!"); self.i.set(self.i.get() - 1);
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}
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}
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impl<'a> shrinky_pointer<'a> {
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pub fn look_at(&self) -> isize { return self.i.get(); }
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}
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fn shrinky_pointer(i: &Cell<isize>) -> shrinky_pointer {
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shrinky_pointer {
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i: i
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}
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}
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pub fn main() {
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let my_total = &Cell::new(10);
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{ let pt = shrinky_pointer(my_total); assert_eq!(pt.look_at(), 10); }
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println!("my_total = {}", my_total.get());
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assert_eq!(my_total.get(), 9);
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}
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