[Haskell-cafe] To "instance C D", GHCI responds that C "is applied to too many type arguments".

jeff@jeffLenovUbu:~$ ghci -XNullaryTypeClasses GHCi, version 7.8.4: http://www.haskell.org/ghc/ :? for help Loading package ghc-prim ... linking ... done. Loading package integer-gmp ... linking ... done. Loading package base ... linking ... done. Prelude> class C Prelude> data D = DConstructor Prelude> instance C D <interactive>:4:10: ‘C’ is applied to too many type arguments In the instance declaration for ‘C D’ Prelude>