> On Nov 15, 2016, at 8:53 AM, Rick Mann <[email protected]> wrote:
>
>
>> On Nov 14, 2016, at 22:51 , Charlie Monroe via swift-evolution
>> <[email protected]> wrote:
>>
>> One major example is the NS/UITableViewDataSource or Delegate - there are
>> many many methods that you don't need to implement, hence are optional.
>>
>> But I think that this was partially solved by default implementation of
>> protocol methods, which pretty much does what you want...
>
> I just realized I only responded to someone else, and not the whole list. It
> does, but it forces me to make the return value of the protocol method
> optional, so that the default implementation can return nil.
You'd still get an optional even with @optional protocol methods:
@objc
protocol Foo {
@optional func bar() -> Int
}
let x = foo.bar?() // x is Int?
Nevertheless, in the previous example:
> var titleForRow:((_ indexPath:IndexPath)->(String))? { get }
You can return String? in the closure instead and the default implementation
can simply return a closure that returns nil. This is pretty much equivalent.
> In the end, I guess that's not so bad, since I'm not happy with the entire
> approach, but it'll do for now.
>
> --
> Rick Mann
> [email protected]
>
>
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