32 lines
875 B
Rust
32 lines
875 B
Rust
// Copyright 2014 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::Cell;
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struct Foo {
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x: int
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}
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impl Clone for Foo {
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fn clone(&self) -> Foo {
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// Using Cell in any way should never cause clone() to be
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// invoked -- after all, that would permit evil user code to
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// abuse `Cell` and trigger crashes.
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fail!();
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}
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}
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pub fn main() {
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let x = Cell::new(Foo { x: 22 });
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let _y = x.get();
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let _z = x.clone();
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}
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