Injecting NgModules and module initialization

Angular instantiates NgModules and registers them with dependency injection. This means that you can inject modules into other modules or components, like this:

@NgModule({
  imports: [TalksModule]
})
class AppModule {
  constructor(t: TalksModule) {}
}

This can be useful for coordinating the initialization of multiple modules, as shown here:

@NgModule({
  imports: [ModuleA, ModuleB]
})
class AppModule {
  constructor(a: ModuleA, b: ModuleB) {
    a.initialize().then(() => b.initialize());
  }
}