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Date: Sun, 22 Feb 2015 19:58:38 +1100
Subject: Re: Design thought for callbacks
From: Chris Angelico <rosuav@gmail.com>
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On Sun, Feb 22, 2015 at 7:34 PM, Marko Rauhamaa <marko@pacujo.net> wrote:
> Chris Angelico <rosuav@gmail.com>:
>
>> Or (a very common case for me) a callback saying "remote end is gone"
>> (eg on a socket) might wipe out the callbacks, thus removing their
>> refloops.
>
> Refloops are not to be worried about, let alone removed.

Why? They force the use of the much slower cycle-detecting GC, rather
than the quick and efficient CPython refcounter. I don't know how
other Pythons work, but mark-and-sweep has its own costs, and I don't
know of any system that's both prompt and able to detect refloops.
Helping it along means your program doesn't waste memory. Why such a
blanket statement?

ChrisA