What's left to do for a stable D2?

[Don]

Andrei Alexandrescu wrote:
> Don wrote:
>> Andrei Alexandrescu wrote:
>>> Eldar Insafutdinov wrote:
>>>> Jesse Phillips Wrote:
>>>>
>>>>> Jason House wrote:
>>>>>
>>>>>> Andrei's finishing his last TDPL chapter, Sean is updating 
>>>>>> std.thread(?), and Walter's been fixing forward reference and CTFE 
>>>>>> bugs. What's left? 
>>>>> This page[1] has been getting regular updates, so it should do a good
>>>>> job answering the question.
>>>>>
>>>>> 1. 
>>>>> http://www.prowiki.org/wiki4d/wiki.cgi?LanguageDevel#FutureDirections
>>>>
>>>>
>>>> From this list: default struct constructors?
>>>
>>> Walter doesn't want. This will go down as one of the larger language 
>>> incapabilities.
>>>
>>> Andrei
>>
>> What's the reason? Does he dislike the concept, or feel it's a 
>> implementation disaster, or something else?
> 
> There are concerns about implementation difficulty and also about 
> muddying other parts of the language, e.g. T.init may fail.

Good to know.
I think not having struct default constructors muddies some other 
things, though. For example, I don't see the point of struct invariants 
if it's possible to create a struct which doesn't obey the invariant.

I think the semantics of T.init are a bit doubtful already. Consider 
that floats default init to NaN, and char.init is not a valid UTF 
character. I don't think the existing T.init is trouble-free.