Создание js-модуля с пространством имен

namespace-module.js

;(function(global, utils) {

  utils.namespace = function(namespace, closure) {
    closure.call(
      null,
      namespace
        .split('.')
        .reduce(
          function(parent, current, index, keys) {
            if(!parent.hasOwnProperty(current)) parent[current] = {};
            return parent.current;
          },
          global
        );
    );
  };

}(this, (this.utils = this.utils || {}));

// usage

utils.namespace('foo.bar.baz', function(baz) {
  // baz is `window.foo.bar.baz`
});

utils.namespace('path.to.app', function(app) {
  // app is `window.path.to.app`
});


//
function namespace(ns) {
    var names = ns.split('.');
    if (names[0] === 'app') names = names.slice(1);
    return names.reduce(function(prev, current) {
        if(!prev.hasOwnProperty(current)) prev[current] = {};
        return prev[current];
    }, (window.app = window.app || {}));
}