Smart pointers instead of GC?

[Namespace]

On Sunday, 2 February 2014 at 16:55:35 UTC, Andrei Alexandrescu 
wrote:
> On 2/2/14, 3:23 AM, JR wrote:
>> On Sunday, 2 February 2014 at 05:30:02 UTC, Andrei 
>> Alexandrescu wrote:
>>> On 2/1/14, 8:18 PM, Frank Bauer wrote:
>>>> On Sunday, 2 February 2014 at 03:38:03 UTC, Andrei 
>>>> Alexandrescu wrote:
>>>>> Whoa, this won't work without an explosion in language 
>>>>> complexity.
>>>>>
>>>>> Andrei
>>>>
>>>> Only daydreaming ...
>>>
>>> No, it's a nightmare.
>>>
>>> Andrei
>>
>> So, going forward, what would you say is the preferred 
>> direction to
>> strive toward?
>>
>> I *seem* to remember reading here that you and Walter were 
>> increasingly
>> growing to favor ARC, but I can't find the post. (Memory 
>> bitrot on my
>> part is more than likely.)
>
> I think of the following foci for the first half of 2014:
>
> 1. Add @nullable and provide a -nullable compiler flag to 
> verify it. The attribute is inferred locally and for white-box 
> functions (lambdas, templates), and required as annotation 
> otherwise. References not annotated with @nullable are 
> statically enforced to never be null.
>
> 2. Work on Phobos to see what can be done about avoiding 
> unnecessary allocation. Most likely we'll need to also add a 
> @nogc flag.
>
> 3. Work on adding tracing capabilities to allocators and see 
> how to integrate them with the language and Phobos.
>
> 4. Work on the core language and druntime to see how to 
> seamlessly accommodate alternate GC mechanisms such as 
> reference counting.
>
>
> Andrei

Sounds good. But why @nullable instead of C# choice of "Type?" ?