> the only way to do all three would be to have a base class and list that I think the Swift way would be enum FooError: Error { case myError(MyEr

> the only way to do all three would be to have a base class and list that I think the Swift way would be enum FooError: Error { case myError(MyError) case badError(BadError) case thirdError(ThirdError) } and declare your function as throws(FooError). That forces handlers of those exceptions to consider all cases. Edit: I think there’s a case for having the compiler synthesize that if one writes something like throws(MyError||BadError||ThirdError), but I’m not sure I’d would like to have such magic. Would two functions with such a declaration throw the same type of exception? That might matter if you do stats on exceptions logged, for example)