making a Set

hi there, I'm tryng to get my concepts right here.. can you please help in defining a funtion like makeSet :: (a->Bool)->Set a I understand that we need a new type Set like data Set a = Set (a->Bool) what puzzles me is how to apply the funtion to all elements belonging to type a. [a] refers to a list of any type, similarly how to access all elements of type a. All help will be greatly appreciated.. _________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.