> Am 24.06.2016 um 07:59 schrieb J. Charles M. N. via swift-evolution 
> <[email protected]>:
> 
> Doesn't Optional.None allready a placeholder for null values in swift?

Not really. What is the type of Optional.none? `let empty = Optional.none` does 
not compile, it says "Generic parameter 'Wrapped' could not be inferred". 
NSNull() is a unique concrete value, and it's compatible with Objective C, 
NSObject and AnyObject. We could of course use `Optional<Int16>.none`, but 
someone else may use `Optional<AnyObject>.none` instead. The extra type 
information is just misleading in this case.

> 
> I read some where that nil was the new way to represent null pointer in 
> swift. 

It is, usually. But does it work in this case?

-Michael

> 
> --
> J. Charles 
> 
>> Le 24 juin 2016 à 00:59, Michael Peternell via swift-evolution 
>> <[email protected]> a écrit :
>> 
>> I think NSNull() should be used, not a struct. I don't think that a struct 
>> would be more performant. Or maybe the performance doesn't matter at all in 
>> any real-world usage scenario. But you may write a benchmark of a realistic 
>> (!) use-case (!) if you think otherwise... would be interesting to see the 
>> results.
>> 
>> Keeping with NSNull() also simplifies objc-interoperability.
>> 
>> -Michael
>> 
>>> Am 23.06.2016 um 06:14 schrieb Alsey Miller via swift-evolution 
>>> <[email protected]>:
>>> 
>>> Add a struct Null to the Swift 3.0 Foundation value types. As a struct, 
>>> Null is more performant (no ARC or memory allocation) than NSNull, and will 
>>> be needed for Swift JSON decoders and libraries that want to use struct 
>>> value types, and be free from classes for their model layer.
>>> 
>>> 
>>>   Coleman,
>>> 
>>> 
>>> 
>>> 
>>> 
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