How templates work (bonus) - Full instantiation of Iota!(1,5)

[Stanislav Blinov]

On Thursday, 4 June 2020 at 11:33:48 UTC, Stefan Koch wrote:
> As part of my series of templates
> I have done a a full instantiation of Iota!(1,5).
> (By hand!)
> And here is the result:
>
> // ...
>
> Because it has been done manually there are probably some bugs.
> Can you find them all?

Is that really full? I.e. you're not counting the instantiations 
of Seq on purpose? :)

If I understand correctly, the below (basically manually written 
version of std.meta.aliasSeqOf) would just be Iota!(1, 5) => Iota?

template Iota(size_t first, size_t last) {
     struct Result {
         static foreach (i; first .. last)
             mixin("auto e", i, " = ", i, ";");
     }
     enum Iota = Result.init.tupleof;
}