[dragonwriter]

> but it I will agree it's a bit dirty that sometimes you do need to rely on standard library functionality rather than language constructs if you want to do these things

You don't need to introduce a Fiber or rely on the standard library, you can just use the core language, leveraging the fact that code in ensure sections gets called even when you are returning "past" the calling method.

(You may need a dirty catch-all rescue so you can set a flag before reraising that lets you distinguish "bypassing direct return by exception" from "bypassing direct return by break or proc-semantics return", but that's still the core language, not standard library.)

I put example code in another comment: https://news.ycombinator.com/item?id=44065226

[vidarh]

Ah, of course. I'm embarassed I didn't think of that now... That's absolutely better than abusing Fiber. Great suggestion.