E0241

? on a value that is neither a Result nor an Option. Spans the ? expression.

Machine-applicable fix: none.

Example

This program fails with E0241.

fn first() -> Option<Int> {
    let n = 1?
    Some(n)
}

Fixed

The same program, fixed.

fn first() -> Option<Int> {
    let n = 1
    Some(n)
}

Listed in the checker notes. oskac explain E0241 prints this entry offline.

All error codes