ob_refcnt INCREF and so on...

Michael Hudson mwh21 at cam.ac.uk
Sun May 28 00:00:49 CEST 2000


Courageous <jkraska1 at san.rr.com> writes:

[snip]
> Can someone confirm or deny this, and if I'm mistaken, explain why
> the refcnt of the object is 2 at the point where I print it??????
> 
> If correct, is there a predictable time when the temporary will
> lose it's reference hold on the object?

YHBT-M (You Have Been Time-Machined):

>>> print sys.getrefcount.__doc__ 
getrefcount(object) -> integer

Return the current reference count for the object.  This includes the
temporary reference in the argument list, so it is at least 2.
>>>

The reference will go away after the function returns.  Read the
source for the CALL_FUNCTION opcode(s if you're in 1.6aX) for the gory
(and I do mean gory) details.

The comment isn't strictly true, either:

>>> class C:
...  pass
... 
>>> sys.getrefcount(C())
1
>>> 

HTH,
Michael

-- 
3. Syntactic sugar causes cancer of the semicolon.
  -- Alan Perlis, http://www.cs.yale.edu/homes/perlis-alan/quotes.html



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