pprConDecl (ConDecl { con_names = cons, con_explicit = expl, con_qvars = tvs
                    , con_cxt = cxt, con_details = PrefixCon arg_tys
                    , con_res = ResTyGADT _ res_ty, con_doc = doc })
  = ppr_mbDoc doc <+> ppr_con_names cons <+> dcolon <+>
    sep [pprHsForAll expl tvs cxt, ppr (foldr mk_fun_ty res_ty arg_tys)]
  where
    mk_fun_ty a b = noLoc (HsFunTy a b)
pprConDecl (ConDecl { con_names = cons, con_explicit = expl, con_qvars = tvs
                    , con_cxt = cxt, con_details = PrefixCon arg_tys
                    , con_res = ResTyGADT _ res_ty, con_doc = doc })
  = ppr_mbDoc doc <+> ppr_con_names cons <+> dcolon <+>
    sep [pprHsForAll expl tvs cxt, ppr (foldr mk_fun_ty res_ty arg_tys)]
  where
    mk_fun_ty a b = noLoc (HsFunTy a b)
pprConDecl (ConDecl { con_names = cons, con_explicit = expl, con_qvars = tvs
                    , con_cxt = cxt, con_details = PrefixCon arg_tys
                    , con_res = ResTyGADT _ res_ty, con_doc = doc })
  = ppr_mbDoc doc <+> ppr_con_names cons <+> dcolon <+>
    sep [pprHsForAll expl tvs cxt, ppr (foldr mk_fun_ty res_ty arg_tys)]
  where
    mk_fun_ty a b = noLoc (HsFunTy a b)