-- including all the friendships is just a monadic fold
mergeFriendships :: [(Name, Name)] -> State ()
-mergeFriendships pairs = foldM_ includeFriendshipM () pairs
+mergeFriendships pairs = foldM_ includeFriendship () pairs
-includeFriendshipM :: () -> (Name, Name) -> State ()
-includeFriendshipM _ (thisPerson, thatPerson) = do
+includeFriendship :: () -> (Name, Name) -> State ()
+includeFriendship _ (thisPerson, thatPerson) = do
include thisPerson
include thatPerson
thisExemplar <- exemplar thisPerson