closure.js

var cdClosure = function() {
  var index;

  function log() {
    console.log(index);
  }

  function iterate() {
    log();

    if (index>1) setTimeout(iterate, 1000);
    index--;
  }

  function countdown(){
    index = 10;
    iterate();
  }

  return function() {
    return countdown();
  }

}();

cdClosure();