Why do some language-defined attributes have @ and some not?

[Gary Willoughby via Digitalmars-d-learn]

On Friday, 24 October 2014 at 15:06:25 UTC, Ola Fosheim Grøstad 
wrote:
> I agree that "@"-stuff is trivial, but I don't think Python 
> sets a good example. The codebase is basically divided in two, 
> libraries have to support both, and I think they should have 
> changed more if going to the trouble.

Yes, Python has a real problem with this.

I would like to see a proper deprecation path implemented in D. I 
don't want my code breaking but i'm willing to accept *informed* 
deprecation, followed by removal. Even if this process takes 
place over a few years.