| ("-d"|"-display") :: rem -> display (get_terms ())
| ("-t"|"-typeof") :: arg :: rem -> pp_type_of arg; parse rem
| ("-l"|"-levels") :: rem -> levels (get_terms ())
| ("-d"|"-display") :: rem -> display (get_terms ())
| ("-t"|"-typeof") :: arg :: rem -> pp_type_of arg; parse rem
| ("-l"|"-levels") :: rem -> levels (get_terms ())