C.R., you are asking for group membership inheritence to flow from parent to child -- any member of a parent group automatically becomes a member of any component sub-group -- which is opposite to how the groups system currently works.
I guess I'm really confused then. I read the docs over again this morning and I think I've been laboring under the misconception that you could have both a group with a sub-group as a component and a group with a group as a member.
What are you trying to model? There is probably a differnt way to do it.
Well, what we were trying to do was come up with a way that we could easily restrict sections of our website to collections of people without having to exhaustively list all the groups that should have access.
For example, say we have the following groups: Site Members, Administrative Staff, Chairpersons. Since I thought you could relate groups together with either a composition or a membership relation, and the composition relation caused permissions to be transitive but not membership, I figured we would create a group called "authorized-users-content" that would contain the groups Site Members, Administrative Staff, and Chairpersons. Then when we needed to see if a visiting user could see protected content we would see if he had the appropriate permissions via the authorized-users-content group. In addition sometimes we have people who need to see protected content but don't fit into any of the other three groups--then we would just add them as members to the authorized-users-content group.
So I think our modelling is still OK. I can't think of a reason why this would not work, unless we can't make one group a member of more than one other group.
