Hi all, I've written a small type class that is meant to behave a bit like Show: class Show a => Echo a where echo :: a -> String echoList :: [a] -> String echoListSep :: a -> String echo = show echoListSep _ = " " echoList [] = "" echoList [x] = echo x echoList (x:xs) = echo x ++ echoListSep x ++ echoList xs instance Echo Char where echo c = [c] echoListSep _ = "" instance Echo a => Echo [a] where echo = echoList instance Echo Int where instance Echo Integer where instance Echo Double where instance Echo Float where gen = map (const 1) f xs = map echo $ gen xs However the code doesn't compile on the last line. But it does compile if I replace 'echo' with 'show'. What's missing to make my typeclass behave like Show and accept input of any type (besides all the missing instances...)? I looked at the code for Show but I didn't see anything that looked "magical"... Thanks, Patrick -- ===================== Patrick LeBoutillier Rosemère, Québec, Canada