if one picks BoxA (member of BoxFam) and pairs it with CircleA one should be able to say for each paired BoxFam, pick CircleA or for each paired BoxFam, pick CircleFam or for each paired BoxA, pick CircleFam etc
really. well now, it would be nice to get official comment on this. not good to be in the dark, makes users not use it even tho it could work if done a certain way or things are avoided when using it. its what i believe anyway.
I'm not sure if I read this topic right but if you mean containers should be able to work with families then yes, I agree. I can see the challenges to implementing that of course. The code would work differently or break entirely if 1 member of the family didn't have the corresponding contained object.
Edit: would probably be better to just use an ID value like I've been doing.