Re: Design thought for callbacks

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Subject	Re: Design thought for callbacks
From	Cem Karan <cfkaran2@gmail.com>
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Date	Sun, 22 Feb 2015 07:16:14 -0500
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To	Marko Rauhamaa <marko@pacujo.net>, Steven D'Aprano <steve+comp.lang.python@pearwood.info>
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On Feb 21, 2015, at 12:08 PM, Marko Rauhamaa <marko@pacujo.net> wrote:

> Steven D'Aprano <steve+comp.lang.python@pearwood.info>:
> 
>> Other than that, I cannot see how calling a function which has *not*
>> yet been garbage collected can fail, just because the only reference
>> still existing is a weak reference.
> 
> Maybe the logic of the receiving object isn't prepared for the callback
> anymore after an intervening event.
> 
> The problem then, of course, is in the logic and not in the callbacks.

This was PRECISELY the situation I was thinking about.  My hope was to make the callback mechanism slightly less surprising by allowing the user to track them, releasing them when they aren't needed without having to figure out where the callbacks were registered.  However, it appears I'm making things more surprising rather than less.

Thanks,
Cem Karan

Thread

Re: Design thought for callbacks "Frank Millman" <frank@chagford.com> - 2015-02-21 07:41 +0200
  Re: Design thought for callbacks Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-02-22 03:15 +1100
    Re: Design thought for callbacks Marko Rauhamaa <marko@pacujo.net> - 2015-02-21 19:08 +0200
      Re: Design thought for callbacks Cem Karan <cfkaran2@gmail.com> - 2015-02-22 07:16 -0500
        Re: Design thought for callbacks Marko Rauhamaa <marko@pacujo.net> - 2015-02-22 14:46 +0200
          Re: Design thought for callbacks Cem Karan <cfkaran2@gmail.com> - 2015-02-22 09:17 -0500
      Re: Design thought for callbacks Laura Creighton <lac@openend.se> - 2015-02-22 13:52 +0100
      Re: Design thought for callbacks Cem Karan <cfkaran2@gmail.com> - 2015-02-22 09:10 -0500
    Re: Design thought for callbacks "Frank Millman" <frank@chagford.com> - 2015-02-22 08:44 +0200
      Re: Design thought for callbacks Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2015-02-22 23:15 +1300
        Re: Design thought for callbacks Cem Karan <cfkaran2@gmail.com> - 2015-02-22 09:22 -0500
          Re: Design thought for callbacks Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2015-02-24 18:45 +1300
            Re: Design thought for callbacks Cem Karan <cfkaran2@gmail.com> - 2015-02-24 06:06 -0500
        Re: Design thought for callbacks Ian Kelly <ian.g.kelly@gmail.com> - 2015-02-22 23:57 -0700

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