| #export(THIS_OBJECT_DOES_NOT_EXIST) # -> installation fails | |
| exportClasses(THIS_CLASS_DOES_NOT_EXIST) | |
| exportMethods(THIS_GENERIC_DOES_NOT_EXIST) | |
| ## these directives only fail (during package installation) | |
| ## if the package actually defines any S4 classes/methods, | |
| ## otherwise the directives are silently ignored | |