having a trivial anonymous function call in template prevents compilation?

[Cauterite via Digitalmars-d-learn]

On Wednesday, 17 August 2016 at 13:18:06 UTC, Adam D. Ruppe wrote:
> Best you can do is use them in an alias argument directly, but 
> you cannot use them in an enum argument.

I think you missed the point; it works perfectly fine without 
having this `({return 0;})()` in the template body (which, as far 
as I can see, doesn't appear to interact at all with the template 
argument).