29 lines
792 B
Rust
29 lines
792 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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#![feature(box_syntax)]
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fn borrow<F>(v: &isize, f: F) where F: FnOnce(&isize) {
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f(v);
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}
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fn box_imm() {
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let mut v: Box<_> = box 3;
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borrow(&*v,
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|w| { //~ ERROR cannot borrow `v` as mutable
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v = box 4;
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assert_eq!(*v, 3);
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assert_eq!(*w, 4);
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})
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}
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fn main() {
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}
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