[swift-evolution] Require parameter names for ENUM Associated Types?

[Tony Allevato]

I suppose I'm not seeing why it's important to exclude the associated
values from pattern matching. What do you gain except saving a few
characters? What you're suggesting doesn't strike me as a significant
improvement over this:

```
case javascript(String, scope: Document?)
...

switch self {
  case .javascript(_, scope: .none): return 0x0D
  case .javascript: return 0x0F   // or case .javascript(_, scope: .some),
if you want to be explicit about the distinction between the two cases
}
```


On Tue, Nov 29, 2016 at 8:12 AM Adrian Zubarev <
adrian.zubarev at devandartist.com> wrote:

> As I said before, the associated values can be excluded for pattern
> matching. I believe this way you can check against the enum case without
> producing any copy of the associated types right?!
>
> var _kind: Byte {
>
>     switch self {
>
>     …
>     case .javaScript:       return 0x0D
>     case .scopedJavaScript: return 0x0F
>     …
>     }
> }
>
> Assume we could overload the values by including additional labels to the
> enum case.
>
> case javaScript(String)
> case javaScript(String, scope: Document) // or more swifty `javascript(String, withScope: Document)`
>
> Now I could check the case like this to solve the ambiguity.
>
> switch self {
>
> …
> case .javaScript:               return 0x0D
> case .javaScript(_:withScope:): return 0x0F
> …
> }
>
> Plus I don’t want to wrap values in optionals when there is no need for
> that.
>
>
>
> --
> Adrian Zubarev
> Sent with Airmail
>
> Am 29. November 2016 um 17:03:12, Tony Allevato (allevato at google.com)
> schrieb:
>
> Why not:
>
> ```
> case javascript(String, scope: Document?)
> ```
>
> Your desired scenario looks like it's conceptually expressing that
> Document is optional, so why not use the type to codify that?
>
> On Tue, Nov 29, 2016 at 7:59 AM Adrian Zubarev via swift-evolution <
> swift-evolution at swift.org> wrote:
>
> Hmm, I feel like default values wouldn’t work with overloaded enum cases.
>
> In my own project I have something like this:
>
> case javaScript(String)
> case scopedJavaScript(String, scope: Document)
>
> // But I'd like it to be:
> case javaScript(String)
> case javaScript(String, scope: Document)
>
>
>
> --
> Adrian Zubarev
> Sent with Airmail
>
> Am 29. November 2016 um 16:55:52, Charles Srstka (cocoadev at charlessoft.com)
> schrieb:
>
> On Nov 29, 2016, at 9:52 AM, Adrian Zubarev via swift-evolution <
> swift-evolution at swift.org> wrote:
>
>
> I just showed a direction of what could be possible.
>
> Personally I think it would be enough if we had this:
>
> enum MyEnum {
>
>     case a
>     case b(Int)
>     case b(Int, string: String)
> }
>
> Where .b can be overloaded by it’s associated types.
>
> Or default values:
>
> enum MyEnum {
> case a
> case b(Int, string: String = “SomeDefault”)
> }
>
> Charles
>
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>
>
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