> (make (while (read "_" "#") (link @)))
> .. I'm not able to get out of the while loop by typing NIL, as the docs
Indeed, you found a bug (thanks again!).
'NIL' is not recognized, and a new symbol with that name gets created.
This happens only in the 32-bit version, the 64-bit version behaves
It will be fixed with the next testing release (due in a few days). For
now, please use '""' (empty string) instead of 'NIL'.