30 lines
771 B
Rust
30 lines
771 B
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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use std::cell::RefCell;
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use std::gc::{Gc, GC};
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enum maybe_pointy {
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no_pointy,
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yes_pointy(Gc<RefCell<Pointy>>),
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}
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struct Pointy {
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x: maybe_pointy
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}
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pub fn main() {
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let m = box(GC) RefCell::new(Pointy { x : no_pointy });
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*m.borrow_mut() = Pointy {
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x: yes_pointy(m)
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};
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}
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