gistfile1.js

$.extend(obj, (function(){

  function private_function(){...}
  function private_function2(){...}
  
  return {
    public_function:  function() {...},
    public_function2: function() {...}
  }

})());


// ----
$.extend(obj, (function(){

  var private_var = 1;

  function private_function(){...}
  function private_function2(){...}


  function public_function() {...}
  function public_function2() {...}
  
  return {
    func1: public_function,
    func2: public_function2
  }

})());