how can i fix this? Mmmh I really need some haskell type class traingings ;) ============= test file ============================================== module Main where import HList import HOccurs import Control.Monad.Reader class Get a b where get :: a -> b data D1 = D1 Int -- dummy type type ActionMonad a l = forall l. (HOccurs D1 l) => ( ReaderT l IO a ) data CR = CR (ActionMonad Bool ()) instance Get CR (ActionMonad Bool ()) where get (CR a) = a main = do print "test" ============= error ================================================== || [1 of 1] Compiling Main ( uqt.hs, uqt.o ) || uqt.hs|16| 0: || Illegal polymorphic or qualified type: forall l. || (HOccurs D1 l) => || ReaderT l IO Bool || In the instance declaration for `Get CR (ActionMonad Bool ())' ====================================================================== Marc