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// Issue 27282: Example 2: This sidesteps the AST checks disallowing
// mutable borrows in match guards by hiding the mutable borrow in a
// guard behind a move (of the mutably borrowed match input) within a
// closure.
//
// This example is not rejected by AST borrowck (and then reliably
// reaches the panic code when executed, despite the compiler warning
// about that match arm being unreachable.
#![feature(if_let_guard)]
fn main() {
let b = &mut true;
match b {
//~^ ERROR use of moved value: `b` [E0382]
&mut false => {},
_ if { (|| { let bar = b; *bar = false; })();
false } => { },
&mut true => { println!("You might think we should get here"); },
_ => panic!("surely we could never get here, since rustc warns it is unreachable."),
}
let b = &mut true;
match b {
//~^ ERROR use of moved value: `b` [E0382]
&mut false => {}
_ if let Some(()) = {
(|| { let bar = b; *bar = false; })();
None
} => {}
&mut true => {}
_ => {}
}
}
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