Example of that/self workaround

that_self_ex.js

var JSobj = function(id) {
  var that = this;
  var date = new Date();
  
  that.id = 'JSnode_' + id;
  that.element = document.getElementById(id);
  that.createdAt = date.getTime();

  that.element.addEventListener('click', clickCallback, false);

  function clickCallback(evt) {
    // 'this' is an object on which we call the function
    // 'that' is always the reference to prototype object

    // log id of the HTML element
    console.log('HTML id -> ' + this.id); 

    // log id we've given to the JS object ('JSnode_HTMLid')
    console.log('JS id -> ' + that.id);

    // log time of creation
    console.log('created at -> ' + that.createdAt);
  }
}

var divEl = new JSobj('cont');
// it will log:
// HTML id -> cont
// JS id -> JSnode_cont
// created at -> 331305814994963