DIP54 : revamp of Phobos tuple types

[Dicebot]

On Monday, 30 December 2013 at 04:25:22 UTC, Timon Gehr wrote:
> If you are going to claim that this is not proper creation of 
> an instance of a type, except that:
>
> int x;
> static assert(is(typeof(x)==int));
>
> Seq!(int, double) y;
> static assert(is(typeof(y)==Seq!(int, double))); // presumably 
> "bad"
>
> Then I don't know what to tell you. It is not useful at all to 
> make a terminological distinction between the two cases above 
> and claim that one is somehow special and confusing, when 
> everything actually behaves in an uniform way.

Same as type list is not type but list of types, expression list 
is not an instance but list of aliases to instances. This is 
important distinction terminology-wise at least and pretty much 
the reason this thing has no ABI which is huge semantical thing 
on its own.

I'd love it to be designed and implemented in such way (I have 
even posted such proposal in past) but it is not the case for 
both DMD and spec right now. I am not an expert in DMD internals 
so I am taking Don's word on this (we have been talking on this 
topic some time ago in person).