```dart
Module module;
if (ref.annotation.module is Type) {
  module = parentInjector.createChild([new Module()..type(ref.annotation.module)]).get(ref.annotation.module);
} if (ref.annotation.module is Function) {
  Module module = ref.annotation.module();
} else {
  throw 'must be Type or Function';
}
nodeModule.install(module);