From: Jesse Jones (jejones_at_[hidden])
Date: 2000-11-20 20:14:26
>If however, the callback can trigger a series of events in other
>objects in the program which change ratically over the life of the
>program, the SigC style tracking becomes a requirement. Event
>queue, multicast, and GUI programs tend to stress these aspects.
>If every time a GUI programmer wanted to shut down a window
>they had to go back and find all the places which they passed
>a closure using that object (and all of the copies those
>using objects made in adaptors) then the user would likely
>tear their hair out. Given that SigC requiring one
>thing in the base class is really minor.
I dunno. I've done quite a bit of GUI programmin with "dumb" callbacks and
I've never needed a callback that got updated when the target went away. I
think the stuff you've been talking about is well worth considering, but
IMO it should be built upon a simple, general, non-invasive callback class.
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