closured_object.js

var closuredObjects = [/*put a bunch of objects that need a closure here*/];

closuredObjects.forEach(function(item){
   var invisibleProperties = {};
   item.get = function(key){
     return invisibleProperties[key];
   };
   item.set = function(key, value){
     invisibleProperties[key] = value;
     return value;
   };
});