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1 point by Pauan 3173 days ago | link | parent

Quite possibly. It should work in my interpreter, though. Actually, () and nil are two different values, but they're special-cased to be eq to each other. It was the only way I found to make one print as "nil" and the other print as "()" From an external point of view, though, they should seem the same.

Also, if = doesn't work, assign probably would:

  (assign nil '())
I just tested it in my interpreter:

  (assign nil 'foo) -> foo
  nil               -> foo
  'nil              -> nil
  ()                -> ()
  '()               -> nil
  (assign nil '())  -> nil
  (is nil ())       -> t
  
So yes, it should be possible to recover, even after overwriting nil (at least in my interpreter. I don't know about MzScheme)