Detecting var globals. Create by Remy Sharp

detect-global.js

(function (global) {
 
  function Globals () {}
 
  var getWindow = function () {
    var iframe = document.createElement('iframe')
    iframe.style.display = 'none'
    document.body.appendChild(iframe)
 
    var result = iframe.contentWindow || iframe.contentDocument
 
    iframe.parentElement.removeChild(iframe)
 
    return result
  }
 
  Globals.prototype.get = function() {
    var iframeWindow = getWindow()
    var result = []
    var property;
 
    // Window
    for (property in global) {
      if (!(property in iframeWindow)) {
        result.push(property)
      }
    }
 
    return result
  };
 
  global.globals = new Globals();
 
}(window));