Passing $ as a function argument

[Dejan Lekic]

On Thursday, 11 October 2018 at 06:58:08 UTC, Simen Kjærås wrote:
>
> unittest {
>     auto x = fun($); // What does it even mean?
> }

After some reading through the whole thread I think his "$ idea" 
can only be applied to a RandomAccessRange (and similar) where 
the size can be known...