SOURCE

var sign = (function() {
  var instance;
  function init() {
    function privateM() {
      console.log('pri');
    }

    var private = 'im also private';

    var privateRan = Math.random();

    return {
      public: function() {
        console.log('public');
      },
      publicPro: 'im also public',

      getRandom: function() {
         return privateRan;
      }
    }
  }
	
	return {
	  getIn:function(){
	    if(!instance){
				instance=init();
			}
			return instance;
    }
    
	}					

})();