private static void processType(@NotNull PsiType type, @NotNull PsiTypeVisitor<? extends PsiType> visitor, @NotNull Set<? super PsiType> typeSet) {
    PsiType accepted = type.accept(visitor);
    if (accepted != null) typeSet.add(accepted);
  }
private static void processType(@NotNull PsiType type, @NotNull PsiTypeVisitor<? extends PsiType> visitor, @NotNull Set<? super PsiType> typeSet)