darcs patch: Add equating p x y = p x == p y

11 Oct 2006


      Wed Oct 11 15:14:32 BST 2006  Duncan Coutts 
  * Add equating p x y = p x == p y
  Just as useful as the 'comparing' function from Data.Ord,
  but for cases where we check equality rather than ordering.
  Use like: groupBy (equating fst)