Angular Model Pattern - use model in service

ampe-service.ts

@Injectable()
export class TodosService {

  private model: Model<Todo[]>;

  todos$: Observable<Todo[]>;

  constructor(private modelFactory: ModelFactory<Todo[]>) {
    this.model = this.modelFactory.create([]);
    this.todos$ = this.model.data$;
  }
}
    
export interface Todo {
  name: string;
  done: boolean;
}