Hi -

Trying out some stuff, I noticed that

   dd := Dictionary new.
   dd at: nil put: #none.

will raise an error in 3.9a saying that "Dictionaries cannot 
meaningfully key by nil". That makes no sense. Dictionaries can 
perfectly contain nil keys, they always have and they always will.

Could somebody please explain to me why we no longer allow a perfectly 
good key in dictionaries?

Cheers,
   - Andreas