pe (TyApp (TyCon "MutableArray#") [x,y])    = "mkMutableArrayPrimTy " ++ ppType x
                                                   ++ " " ++ ppType y
ppT
ppType (TyApp (TyCon "MutableArray#") [x,y])    = "mkMutableArrayPrimTy " ++ ppType x
                                                   ++ " " ++ ppType y
ppType (TyApp (TyCon "MutableArray#") [x,y])    = "mkMutableArrayPrimTy " ++ ppType x
                                                   ++ " " ++ ppType y