gistfile1.txt

// HTMLElement dataset property
(function checkDatasetProperty() {
  var div = document.createElement('div');
  if ('dataset' in div)
    return; // dataset property exists
  Object.defineProperty(HTMLElement.prototype, 'dataset', {
    get: function htmlElementDatasetGetter() {
      // adding dataset field to the actual object 
      return (this.dataset = {});
    }
  });
})();