harbl/src/Network/DNS/RBL/Reversible.hs

   1 -- | The 'Reversible' typeclass.
   2
   3 module Network.DNS.RBL.Reversible ( Reversible(..) )
   4 where
   5
   6 -- | This class is pretty straightforward. It's for things that you
   7 -- can reverse, or flip around, or make backwards, or however you want
   8 -- to think of it. Our primary application is to hostname components.
   9 --
  10 class Reversible a where
  11   backwards :: a -> a