GreetingModule.kt

@Qualifier annotation class SpecialGreeting1
@Qualifier annotation class SpecialGreeting2

@Module
@InstallIn(SingletonComponent::class)
object GreetingModule {
  @Provides @SpecialGreeting1
  fun provideSpecialGreeting1(): String = "Heeeeey"

  @Provides @SpecialGreeting2
  fun provideSpecialGreeting2(): String = "Oieeeee"

  @Provides @IntoSet
  fun provideEnglishGreeting(): String = "Hello"

  @Provides @IntoSet
  fun provideGermanGreeting(): String = "Hallo"

  @Provides @IntoSet
  fun providePortugueseGreeting(): String = "Olá"

  @Module
  @InstallIn(SingletonComponent::class)
  interface Bindings {
    // This is separate in its own module since it must be abstract
    // and we can't have an abstract method in an object.
    @Binds fun bind(impl: GreetingConcatenatorImpl): GreetingConcatenator
  }
}