go (FunTy a b) = go a `plusNameEnv` go b
go (PredTy (IParam _ ty)) = go ty
go (PredTy (ClassP cls tys)) = go_s tys -- Ignore class
- go (NoteTy _ ty) = go ty
go (ForAllTy _ ty) = go ty
go_tc tc tys | isSynTyCon tc = extendNameEnv (go_s tys) (tyConName tc) tc