+ # we just did this - move on
+ if self.parentof(shared):
+ return False
+
+ # *
+ # /|
+ # * *
+ # |\|
+ # | *
+ # | |
+ # Situation above is ok - what we don't want, is:
+ # *
+ # /|
+ # * |
+ # |\|
+ # | *
+ # | |
+ # We want to prevent stuff like this.
+ if self.parent().parentof(shared):
+ return False