31 lines
1.2 KiB
Rust
31 lines
1.2 KiB
Rust
// Issue 27282: This is a variation on issue-27282-move-ref-mut-into-guard.rs
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//
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// It reborrows instead of moving the `ref mut` pattern borrow. This
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// means that our conservative check for mutation in guards will
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// reject it. But I want to make sure that we continue to reject it
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// (under NLL) even when that conservative check goes away.
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#![feature(if_let_guard)]
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fn main() {
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let mut b = &mut true;
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match b {
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&mut false => {},
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ref mut r if { (|| { let bar = &mut *r; **bar = false; })();
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//~^ ERROR cannot borrow `r` as mutable, as it is immutable for the pattern guard
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false } => { &mut *r; },
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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 mut b = &mut true;
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match b {
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&mut false => {},
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ref mut r if let Some(()) = { (|| { let bar = &mut *r; **bar = false; })();
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//~^ ERROR cannot borrow `r` as mutable, as it is immutable for the pattern guard
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None } => { &mut *r; },
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&mut true => {},
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_ => {},
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}
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}
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