Reimplementing the bulk of std.meta iteratively

[Paul Backus]

On Saturday, 26 September 2020 at 17:30:44 UTC, Stefan Koch wrote:
>
> The PR referenced does not give, actually give you the ability 
> to dereify types within CTFE.
> The PR forces a template and template has to have template 
> parameters to take the mangles.
> I would think that is against the actual goal.

It's against the goal if your goal is for meta-functions to be 
100% monomorphic. But it does accomplish the goal of turning 
template recursion (O(n) instantiations) into flat iteration 
(O(1) instantiations).

Personally, I don't think 100% monomorphism is necessary or 
particularly desirable, so I'm ok with a design that eschews it.