43 lines
1.1 KiB
Rust
43 lines
1.1 KiB
Rust
// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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#![feature(unsafe_destructor)]
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use std::cell::Cell;
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use std::gc::{GC, Gc};
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struct shrinky_pointer {
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i: Gc<Gc<Cell<int>>>,
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}
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#[unsafe_destructor]
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impl Drop for shrinky_pointer {
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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 shrinky_pointer {
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pub fn look_at(&self) -> int { return self.i.get(); }
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}
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fn shrinky_pointer(i: Gc<Gc<Cell<int>>>) -> 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 = box(GC) box(GC) Cell::new(10);
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{ let pt = shrinky_pointer(my_total); assert!((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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