Closure capture

gistfile1.js

(function() {
    var someArray = [1, 2, 3];
    var body = document.querySelector('body');
    body.addEventListener('click', function() {
      // Note: 'someArray' is neither an parameter nor a global variable.
      // Will print '1,2,3' in console when clicking.
      console.log(someArray.join(','));
      // And since this function will be triggered later,
      // you can see closure is accross the time & space (LOL)
    });
})();

 // 'undefined'
console.log(typeof(someArray));
// Since no one outside the closure can access
// things inside.