code: func _main() int {
  
  	var typesOnly bool
  	flag.BoolVar(&typesOnly, "typesOnly", false, "only generate types")
  	flag.Parse()
  
  	apiFile := "./api/api-2.json"
  	var err error
  	if typesOnly {
  		err = genTypesOnlyAPI(apiFile)
  	} else {
  		err = genFull(apiFile)
  	}
  	if err != nil {
  		fmt.Println(err)
  		return 1
  	}
  	return 0
  }
docs: // return-based exit code so the 'defer' works