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Re: contextlib.contextmanager and try/finally

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On Wednesday, January 11, 2012 11:20:19 AM UTC-6, Ian wrote:
> 
> Second, I believe that passage is not referring to the contextmanager
> decorator specifically, but more generally to the changes that were
> made to allow generators to yield from within a try-finally construct
> (previously this would have been illegal syntax, since there was no
> way to guarantee the finally block would be performed).

Thanks.  You and Robert have shown me the light.  That paragraph was talking about the finalization that happens to a suspended generator when it is GC'd.  Meanwhile, the contextmanager decorator ensures that its generator is run all the way through, so it would never be left in a suspended state, so its GC/finalization semantics are irrelevant. (Please correct, if wrong.)

(Neil: I understood that it created a context manager object, but I had been reading the quoted paragraph to mean that by going through a generator the decorator was re-introducing a dependency on GC time.  But I was wrong.)

Regards,
Johann

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contextlib.contextmanager and try/finally johannh@gmail.com - 2012-01-11 07:45 -0800
  Re: contextlib.contextmanager and try/finally Neil Cerutti <neilc@norwich.edu> - 2012-01-11 16:46 +0000
  Re: contextlib.contextmanager and try/finally Robert Kern <robert.kern@gmail.com> - 2012-01-11 17:14 +0000
  Re: contextlib.contextmanager and try/finally Ian Kelly <ian.g.kelly@gmail.com> - 2012-01-11 10:20 -0700
    Re: contextlib.contextmanager and try/finally johannh@gmail.com - 2012-01-11 09:30 -0800
    Re: contextlib.contextmanager and try/finally johannh@gmail.com - 2012-01-11 09:30 -0800
  RE: contextlib.contextmanager and try/finally "Prasad, Ramit" <ramit.prasad@jpmorgan.com> - 2012-01-31 21:07 +0000
  RE: contextlib.contextmanager and try/finally Peter Otten <__peter__@web.de> - 2012-01-31 23:02 +0100
  Re: contextlib.contextmanager and try/finally Ian Kelly <ian.g.kelly@gmail.com> - 2012-01-31 15:09 -0700
    Re: contextlib.contextmanager and try/finally Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-02-01 02:15 +0000

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