Design thought for callbacks

[Chris Angelico]

On Sun, Feb 22, 2015 at 7:34 PM, Marko Rauhamaa <marko at pacujo.net> wrote:
> Chris Angelico <rosuav at 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