partial.ts

export type Partial<T> = { [P in keyof T]?: T[P]; };

export interface DefaultConfig {
  searchEnabled: boolean;
  headerEnabled: boolean;
  orderEnabled: boolean;
}

@Injectable()
export class TableService {
  public defaultConfig: Partial<DefaultConfig> = {
    searchEnabled: true,
  };
}

export class TableComponent {
  private additionalConfig: Partial<DefaultConfig> = {
    headerEnabled: true,
    orderEnabled: true,
  };

  ngOnInit() {
    const config = { ...this.defaultConfig, ...this.additionalConfig };
  }
}