[swift-evolution] Proposal SE-0009 Reconsideration

[Vladimir.S]

Oh, cool! This is exactly the same code I was asking the community to 
comment out if this is wanted/expected behavior. Unfortunately no reply was 
given. This is why I suggested a warning if type's method has the same name 
as such protocol extension method in my current thread "[Pitch] Requiring 
special keyword to mark protocol implementation methods"

On 19.05.2016 15:30, Krystof Vasa wrote:
> See this example that demonstrates how it's pretty much unusable (IMHO), since whenever you refer to the instance as to the protocol, the default implementation gets invoked:
>
> protocol MyProtocol { }
>
> extension MyProtocol {
> 	func getInt() -> Int {
> 		return 0
> 	}
> }
>
> class MyClass: MyProtocol {
> 	func getInt() -> Int {
> 		return 1
> 	}
> }
>
>
> let instance = MyClass()
> instance.getInt() // 1
>
> var anyInstance: MyProtocol = instance
> anyInstance.getInt() // 0 !!!!!!!
>
>
> Since anyInstance is of MyProtocol type, you get the default implementation (no dynamic dispatch).
>
> Krystof
>
>> On May 19, 2016, at 2:22 PM, Vladimir.S via swift-evolution <swift-evolution at swift.org> wrote:
>>
>> On 19.05.2016 0:01, Michael Peternell wrote:
>>>> Not Fun To Debug bits (similar to the dispatching rules of protocol
>>>> extensions default methods).
>>> There are dispatching rules of protocol extension default methods? I
>>> thought the methods are selected randomly... just kidding -
>>
>> [offtopic]
>> Could you please describe the joke and the problem of 'dispatching rules of protocol extensions default methods'? Want to clarify this for myself. Thank you.
>> [/offtopic]
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>
> .
>