Check if a variadic argument is numeric?

[Andrea Fontana via Digitalmars-d-learn]

On Thursday, 6 July 2017 at 12:15:56 UTC, Hamborg wrote:
> That compiles, but it returns false when I pass in a numeric 
> value... :(

I think you should provide a code snippet then. I think I missed 
something about your question.

Andrea