eXo.provide(namespace, obj);

eXo.js

(function(w) {
  w.eXo = w.eXo || {};
  /**
   * Exposes a function to attach its to a namespace, this is similar but more advanced than goog.provide(namespace)
   *
   * @param namespace the name space string, for example: "eXo.social.MyClass".
   * @param obj the associated function or singleton object to be associated with this name space
   */
  eXo.provide = function(namespace, obj) {
    if (!namespace || !obj) {
      if (console) {
        console.warn('eXo.provide: namespace or obj is not valid.');
        console.info('namespace: ' + namespace);
        console.info('obj: ' + obj);
      }
      return;
    }
    var names = namespace.split('.');
    var tempNamespace = window;
    for (var i = 0, len = names.length; i < len; i++) {
      if (i == (len - 1)) {
        //the last one
        tempNamespace[names[i]] = obj;
      } else {
        tempNamespace = tempNamespace[names[i]] = tempNamespace[names[i]] || {};
      }
    }
  }
})(window);

//sample with Class
(function(eXo) {
  var MyClass = function() {

  };
  MyClass.prototype.sayHi = function() {
    alert('Hi!');
  };
  //exposes
  eXo.provide('net.hoatle.MyClass', MyClass);
  
  //Without eXo#provide
  /*
   window.net = window.net || {};
   window.net.hoatle = window.net.hoatle || {};
   window.net.hoatle.MyClass = MyClass;
   */                                   
  
})(eXo);

var myClass = new net.hoatle.MyClass();
myClass.sayHi();

//sample with Singleton Object

(function(eXo) {
  var MyObject = {
    sayHi: function() {
      alert('Hi!');
    }
  };

  eXo.provide("net.hoatle.MyObject", MyObject);
})(eXo || window);

net.hoatle.MyObject.sayHi();

// sample with a root namespace

eXo.provide("hoatlevan", {
  sayHi: function() {
    alert('Hi!');
  }
});

hoatlevan.sayHi();

//exception cases => log and return

eXo.provide(null, {});

eXo.provide('abc', null);

eXo.provide(null, null);