Javascript Singleton

singleton.js

var timeZoneService = (function () {
  var instance;
  function init() {
    var prop
    var method = function() {

    }
    return {
        prop:prop,
        method:method
    }
  }

  return {
    getInstance: function () {
      if ( !instance ) {
        instance = init();
      }
      return instance;
    }
  };

})();