Pass variable to IIFE like NodeJS module.exports

Question

I'm trying to pass a variable to a IIFE in another file (a module required ) but it is ignored.

index.js

var modulo = require('./modulo');
modulo.foo = "newFoo";
console.log(modulo.foo);
console.log(modulo.myFunction.innerFunction());

modulo.js

var foo = "oldFoo";
var myFunction = (function(innerFoo) {
  return {
    innerFunction: function () {
      return "Returning innerFunction with " + innerFoo;
    }
  };
})(foo);

module.exports.foo = foo;
module.exports.myFunction = myFunction;

Now when I execute node index.js the result is:

newFoo
Returning innerFunction with oldFoo

How can I pass the newFoo variable so modulo.js can use it internally?

(Actually, I want to pass a socket so my module.js can use it for communication with the server)

Thank you very much in advance!!

EDIT: SOLUTION

modulo.js

module.exports.foo = "";
var myFunction = (function() {

  return {
    innerFunction: function () {
      var innerFoo = module.exports.foo;
      return "Returning innerFunction with " + innerFoo;
    }
  };
})();

module.exports.myFunction = myFunction;

Answer 1

Your IIFE does not read from module.foo , which you are overwriting, but from the actual foo variable in modulo.js . Javascript is Pass-by-value with primitive values ;)