1 error[E0597]: `counter` does not live long enough
2 --> $DIR/issue-54556-niconii.rs:22:20
4 LL | if let Ok(_) = counter.lock() { }
7 | borrowed value does not live long enough
8 | a temporary with access to the borrow is created here ...
13 | `counter` dropped here while still borrowed
14 | ... and the borrow might be used here, when that temporary is dropped and runs the destructor for type `std::result::Result<MutexGuard<'_>, ()>`
16 = note: The temporary is part of an expression at the end of a block. Consider adding semicolon after the expression so its temporaries are dropped sooner, before the local variables declared by the block are dropped.
18 error: aborting due to previous error
20 For more information about this error, try `rustc --explain E0597`.