Signals and Slots in D

[Sean Kelly]

Lutger wrote:
> Walter Bright wrote:
>> Lutger wrote:
>>> Almost, it's very simple, like the plain old function pointer as 
>>> callback in C. The main difference is:
>>> - when an object which has member functions connected gets detroyed, 
>>> there is no problem, no segfaults.
>>
>> Doesn't garbage collection automatically take care of that?
> 
> Yes, but you'd have a reference to a dead object in your delegate array 
> when it gets deleted and then you emit a signal. You can of course 
> remove that reference when you so want to delete an object, then you 
> have to track them and miss some ease of use. Or let some language / 
> library do it for you.

I believe this was one of the reasons people have requested weak 
references for D.  Though really, the same thing can be accomplished by 
registering a proxy class instead of a reference to the class to be 
signaled.  I do this all the time in C++.


Sean