Tracking issue for using it in main: https://github.com/rust-lang/rust/issues/43301

You can mix them if you take your Options and convert them into Results with the Option::ok_or(E) method.

    do_this(x).ok_or(CustomError::ThisError)?;

Also regarding an "early return protocol", I'd also be curious for continue, break, any ! type expression. For one of the Rust projects I worked on, I wrote an unwrap macro on Option that takes a secondary ! argument.

That's coming as well!

Interesting. Looking at the proposal it seems specific to main() and not any void returning function, by automatically picking an exit status. I suppose I worry the construct has a lack of control (log diagnostics, exit status, cleaning, etc) when bailing and can’t handle eg continue, break too.

exit status and cleaning should be just fine, logging or something else would need to not do it, yeah. continue and break would be weird outside of loops.