SuperExtends_es6.js

/**
 * Multiples extends Javascript ES6
 * @About: Clone method's class
**/

class SuperExtends {
  constructor(ar) {
    ar.forEach((item) => {
      const news = new item;

      const arNews = Object.getOwnPropertyNames(news.constructor.prototype);
      arNews.shift();

      arNews.forEach((val) => {
        this.constructor.prototype[val] = news.constructor.prototype[val];
      });
    });
  }
}



/**
 * Using/Example
**/
class Head {
  snout() {}
  mouth() {}
}

class Body {
  core() {}
  stomach() {}
}

class Dog extends SuperExtends {
  constructor() {
    super([Head, Body]);
    
    console.dir(this); //Console in browser: Dog > __proto__
  }
}

new Dog();