> On Jan 11, 2018, at 23:30, Chris Lattner <[email protected]> wrote: > > >> On Jan 11, 2018, at 11:15 PM, Jean-Daniel via swift-evolution >> <[email protected]> wrote: >> >> A question about the new #unknown behavior. Is it intended to be used for >> error handling too ? >> Will it be possible to use in catch clause ? > > If we go with the #unknown approach, then yes of course it will work in catch > clauses. They are patterns, so it naturally falls out.
It will not work in catch clauses because you need to have a static type that's an enum. Catch clauses always (today…) have a static type of 'Error'. > > If we go with the “unknown default:” / “unknown case:" approach, then no, > this has nothing to do with error handling. > > IMO, this pivots on the desired semantics for “unknown cases in enums”: if > you intentionally try to match on this, do we get a warning or error if you > don’t handle all the cases? If we can get to consensus on that point, then > the design is pretty obvious IMO. That's fair. I'm strongly in favor of a warning, though, because again, people don't edit their dependencies. Jordan _______________________________________________ swift-evolution mailing list [email protected] https://lists.swift.org/mailman/listinfo/swift-evolution
