Decorator for unsubscribe Subscriber

DestroySubscribers.ts

import { Subscriber } from "rxjs";

/**
 * @example
 * 
 * @Component({})
 * @DestroySubscribers()
 * export class YourComponent {
 *  createSub: Subscription = new Subscription();
 *  subscribers: Subscription[] = [];
 *  
 *  ownMethod() {
 *    // some code subscribe
 *    this.createSub = blablabla.subscribe(
 *      res => console.log(res)
 *    ); 
 *    this.subscribers.push(this.createSub);
 *  }
 * }
 */
export default function DestroySubscribers() {
  return function (target: any) {
    // decorating the function ngOnDestroy
    target.prototype.ngOnDestroy = ngOnDestroyDecorator(target.prototype.ngOnDestroy);

    function ngOnDestroyDecorator(f) {
      return function () {
        let superData = f ? f.apply(this, arguments) : null;

        // unsubscribing
        for (let subscriberKey in this.subscribers) {
          let subscriber = this.subscribers[subscriberKey];
          if (subscriber instanceof Subscriber) {
            subscriber.unsubscribe();
          }
        }

        // returning the result of ngOnDestroy performance
        return superData;
      }
    }

    // returning the decorated class
    return target;
  }
}