[Python-Dev] Re: Object finalization for local (ie function)scopes

"Martin v. Löwis" martin at v.loewis.de
Mon Jun 14 23:50:18 EDT 2004

Oliver Schoenborn wrote:
> Oh no, absolutely not! The objects are finaly-izated only for the frame
> where created. This is ensured because the cleaner uses a stack (unrelated
> to the frame stack), one item in the stack per function call. You will see
> this clearly if you look at the latest detscope.py. b is cleaned up upon
> return from g, and a will be cleaned up only upon return from f.

While I understand your implementation, I'm uncertain how much of it you
consider normative, and how much is implementation detail. For example,
is the order in which the finally-izers are called significant or not?

Or, coming back to my original question: It appears that *not* all
objects registered with the cleaner are destroyed when the function
returns. This brings me back to my original question: As not all
objects are finally-ized at the end of the function, then *which*
objects precisely are finally-ized?

Let me try guess an answer: At the end of a scope-guarded function,
all need-finally-ization objects are finally-ized that have been
created since the function was invoked, and which haven't yet been

Taking threads into account, this definition is probably not what you
want: likely, you want to see only those objects finally-ized, that
have been created in the context of the thread in which the function
was invoked.

Is that correct? In particular, what happens with need-finally-ization 
objects which whose constructor call does not directly appear in a
scope-guarded function?


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