javascript - JS: revealing module pattern - accessing internal objects vs arrays? -

using revealing module pattern, how can provide direct access non-static private variables? here's have:

var m = function () {     var obj = {};     var arr = [];     var change = function () {         obj = {"key":"if see this, o reference obj"};         arr.push("if see this, reference arr")         };     return {         change: change,         o: obj,         a: arr         }; }();  m.change(); console.log(m.a); // prints ["if see this, reference arr"]  console.log(m.o); // prints object {}, wanted "if see this, o..." 

it seems references arr directly, while o settles copy of obj's value @ initialization time. understand behavior if obj string, float, or boolean.

i of course expose obj via public get_obj method, i'm still curious if can solved without additional methods (i want keep interface obj intact). furthermore, what's special arrays objects don't have, causes behavior?

really grateful insights,

obj["key"] = "if see this, o reference obj"; 

you can set key property obj , keep reference original object.