31 lines
1.2 KiB
Rust
31 lines
1.2 KiB
Rust
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// Copyright 2017 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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// revisions: lxl nll
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//[lxl]compile-flags: -Z borrowck=mir -Z two-phase-borrows
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//[nll]compile-flags: -Z borrowck=mir -Z two-phase-borrows -Z nll
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// This is the first counter-example from Niko's blog post
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// smallcultfollowing.com/babysteps/blog/2017/03/01/nested-method-calls-via-two-phase-borrowing/
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// of a danger for code to crash if we just turned off the check for whether
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// a mutable-borrow aliases another borrow.
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fn main() {
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let mut v: Vec<String> = vec![format!("Hello, ")];
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v[0].push_str({
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v.push(format!("foo"));
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//[lxl]~^ ERROR cannot borrow `v` as mutable more than once at a time [E0499]
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//[nll]~^^ ERROR cannot borrow `v` as mutable more than once at a time [E0499]
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"World!"
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});
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}
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