34 lines
1.3 KiB
Rust
34 lines
1.3 KiB
Rust
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// Copyright 2018 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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// Issue 27282: Example 2: This sidesteps the AST checks disallowing
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// mutable borrows in match guards by hiding the mutable borrow in a
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// guard behind a move (of the mutably borrowed match input) within a
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// closure.
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//
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// This example is not rejected by AST borrowck (and then reliably
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// reaches the panic code when executed, despite the compiler warning
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// about that match arm being unreachable.
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#![feature(nll)]
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fn main() {
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let b = &mut true;
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match b {
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&mut false => {},
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_ if { (|| { let bar = b; *bar = false; })();
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//~^ ERROR cannot move out of `b` because it is borrowed [E0505]
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false } => { },
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&mut true => { println!("You might think we should get here"); },
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//~^ ERROR use of moved value: `*b` [E0382]
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_ => panic!("surely we could never get here, since rustc warns it is unreachable."),
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}
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}
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