Design thought for callbacks
Gregory Ewing
greg.ewing at canterbury.ac.nz
Tue Feb 24 16:19:18 EST 2015
random832 at fastmail.us wrote:
> On Tue, Feb 24, 2015, at 00:20, Gregory Ewing wrote:
>
>>This is why I suggested registering a listener object
>>plus a method name instead of a callback. It avoids that
>>reference cycle, because there is no long-lived callback
>>object keeping a reference to the listener.
>
> How does that help? Everywhere you would have had a reference to the
> "callback object", you now have a reference to the listener object.
The point is that the library can keep a weak reference
to the listener object, whereas it can't reliably keep
a weak reference to a bound method.
--
Greg
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