[OptionOfT]

What about doing something that Java does with the throws keyword? Would that make the checking easier?

[bigfishrunning]

I think that's exactly what's being asked for here (via the "panic effect" that the article refers to)

although, I think i'd prefer a "doesn't panic" effect just to keep backwards compatibility (allowing functions to panic by default)

[3836293648]

Or effect aliases. But given that it's strictly a syntactic transformation it seems like make the wrong default today, fix it in the next edition. (Editions come with tools to update syntax changes)

[mananaysiempre]

Something like that, except you probably also want to be able to express things like “whatever the callback I’m passed can throw, I can throw all of that and also FooException”. And correctly handle the cases when the callback can throw FooException itself, and when one of the potential exceptions is dependent on a type parameter, and you see how this becomes a whole thing when done properly. But it’s doable.