title: How to use this before super?
body: <p>I know that <code>this</code> is not allowed before <code>super</code> but I need to do it. I was wondering if there was a legal way to do this in es6?</p>
  
  <p>My code:</p>
  
  <pre><code>class DOMElement {
    constructor(aNodeName) {
      this.name = aNodeName;
      this.create();
    }
    create() {
      let domref = document.createElement(this.name);
      document.body.appendChild(domref);
      return domref;
    }
  }
  
  class Button extends DOMElement {
    constructor(aLabel) {
      this.label = aLabel;
      super('button');
    }
    create() {
      let domref = super.create();
      domref.textContent = this.label;
    }
  }
  </code></pre>
  
  <p>If I don't set <code>this.label</code> before calling <code>super('button')</code> in <code>Button.prototype.create</code> then <code>domref.textContent</code> is set to <code>undefined</code>.</p>