Mentioning symbol put it to obarray?

[Oleksandr Gavenko]

I execute code:

  (put 'xxx 'some "value")

and found symbol "xxx" in obarray. Also such code always invoke error:

  (mapatoms (lambda (ob) (when (eq ob 'XYZ) (error "ok"))) obarray)

for any "XYZ" because after parsing above line and before evaluation "XYZ"
put to obarray...

So mentioning any symbol make it globally available (existing)?

Is it garbage collected from (remember about link in obarray)?

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Best regards!