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From: Devin Jeanpierre <jeanpierreda@gmail.com>
Date: Sat, 21 Feb 2015 06:24:36 -0800
Subject: Re: Design thought for callbacks
To: Chris Angelico <rosuav@gmail.com>
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On Fri, Feb 20, 2015 at 9:42 PM, Chris Angelico <rosuav@gmail.com> wrote:
> 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.

For that matter, if the callback is a method, you need to hang onto
it, because method wrappers are generated on demand, so the method
would be removed from the valid callbacks instantly.

Weak references for callbacks are broken.

-- Devin