mirror of https://github.com/rust-lang/rust
35 lines
1.1 KiB
Rust
35 lines
1.1 KiB
Rust
// 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(if_let_guard)]
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fn main() {
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let b = &mut true;
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match b {
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//~^ ERROR use of moved value: `b` [E0382]
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&mut false => {},
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_ if { (|| { let bar = b; *bar = false; })();
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false } => { },
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&mut true => { println!("You might think we should get here"); },
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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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let b = &mut true;
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match b {
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//~^ ERROR use of moved value: `b` [E0382]
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&mut false => {}
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_ if let Some(()) = {
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(|| { let bar = b; *bar = false; })();
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None
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} => {}
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&mut true => {}
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_ => {}
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}
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}
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