Private vs public

i feel like im close with this one. i hid the premium users btn but members can still see premium members wikis. im wondering if there is something in the cancan gem that allows for an exclude?
```
if user.role? :member
can :read, Article if current_user.role == 'member'
end
```
that looks clunky though. also the premium-user-btn in wikis/index doesnt work if member is nil...otherwise it seemed like a neat fix.