language feature usage statistics

[Les De Ridder]

On Friday, 18 October 2019 at 19:53:46 UTC, aliak wrote:
> So this is something I've been wondering about for a while. And 
> I don't believe I've seen any compiler with this, but have 
> people ever thought about putting telemetry in compilers? How 
> do people feel about having feature usage stats from dmd?
>
> [...]

I vaguely remember there being a tool that generated such 
statistics
from the source code of packages registered on code.dlang.org, 
but I
might be mistaken.