Interesting work on packing tuple layout

[Andrei Alexandrescu]

On 6/14/20 12:26 PM, Avrina wrote:
> On Sunday, 14 June 2020 at 03:57:40 UTC, Andrei Alexandrescu wrote:
>> On 6/13/20 11:55 PM, Avrina wrote:
>>> On Sunday, 14 June 2020 at 03:08:48 UTC, Andrei Alexandrescu wrote:
>>>> On 6/13/20 7:30 PM, Timon Gehr wrote:
>>>>> Another question is if automatic packing is worth making the layout 
>>>>> harder to predict.
>>>>
>>>> I think so. Size does matter.
>>>
>>> If you are talking about implementing a tuple type into the language,
>>
>> negative
> 
> The situation also applies to the only tuple implementation in D. If you 
> are proposing a new type with emphasis on reducing the footprint of the 
> tuple then I don't see a problem with that. Changing the existing tuple 
> implementation would be problematic.

No. There's no guarantee made by std.tuple as to layout. We can't be 
overly conservative for the sake of supporting code that assumes too much.