Chris Angelico <ros...@gmail.com>: > On Sat, Feb 21, 2015 at 1:44 PM, Cem Karan <cfkar...@gmail.com> wrote:
>> In order to inform users that certain bits of state have changed, I >> require them to register a callback with my code. The problem is that >> when I store these callbacks, it naturally creates a strong reference >> to the objects, which means that if they are deleted without >> unregistering themselves first, my code will keep the callbacks >> alive. Since this could lead to really weird and nasty situations, >> [...] > > No, it's not. I would advise using strong references - if the callback > is a closure, for instance, you need to hang onto it, because there > are unlikely to be any other references to it. If I register a > callback with you, I expect it to be called; I expect, in fact, that > that *will* keep my object alive. I use callbacks all the time but haven't had any problems with strong references. I am careful to move my objects to a zombie state after they're done so they can absorb any potential loose callbacks that are lingering in the system. Marko -- https://mail.python.org/mailman/listinfo/python-list
