> On Jan 10, 2018, at 12:04, Jose Cheyo Jimenez via swift-evolution > <[email protected]> wrote: > > > > On Tue, Jan 9, 2018 at 10:10 PM, Chris Lattner <[email protected] > <mailto:[email protected]>> wrote: > On Jan 9, 2018, at 3:07 PM, Jose Cheyo Jimenez <[email protected] > <mailto:[email protected]>> wrote: > > Hi Chris, > > > > This is great. Thanks for spending time on this! I am in favor of `case > > #unknown` to only match unknown cases. > > > > 1) Would #uknown be available to RawRepresentable structs? > > I haven’t considered this, so I’m not sure how that would work. I had > assumed that this would be an enum specific concept. > > What do you have in mind? If your raw representation is itself an enum, then > of course this would work. > > I was just curious since a RawRepresentable structs ( and OptionSet ) are > very similar to non exhaustive enums in that they would require handling > unknown cases. Currently RawRepresentable is required to use a default even > if all cases are accounted for. > > struct Directions: OptionSet { > let rawValue: UInt8 > static let up = Directions(rawValue: 1 << 0) > } > > let myDir = Directions.up > > switch myDir > { > case .up : print("matched") > default: print("default required") > }
Since an option set has 2^N possible values, not just N, we don't expect anyone to be switching over them! And it wouldn't be correct to try to do so exhaustively anyway. Jordan
_______________________________________________ swift-evolution mailing list [email protected] https://lists.swift.org/mailman/listinfo/swift-evolution
