yet another javascript dependency injector

inject.js

;(function(window, Promise, exports) {
  'use strict';
  var types = {};

  /**
   * Register a type with the injector.
   * @param  {String} name         The name of the type to register.
   * @param  {Function} constructor  The constructor for the injector. Constructors can be regular function; `this` will be bound to the constructor function itself. Constructs may register their dependencies by placing an $inject field that is a string array. Each dependency will be resolved before instantiating the constructor. If the dependency cannot be fulfilled, an Error will be thrown.
   */
  exports.register = function(name, constructor) {
    var bundle = {
      dependencies: constructor.$inject || [],
      constructor: constructor
    };
    types[name] = bundle;
  };


  var resolveQueue = [];
  /**
   * Resolve a type. Note that this function will do nothing until the DOM has been loaded (this allows for the injector to be sure it has found every dependency).
   * @param  {String} name The name of the type to resolve.
   * @return {Promise<Object>}      A promise that will resolve to the resolved object, or reject upon error.
   */
  exports.resolve = function(name) {
    return new Promise(function(resolve, reject) {
      resolveQueue.push(function() {
        var bundle = types[name];
        if(bundle === undefined) {
          reject(new Error('could not find type: '+ name));
          return;
        }
        var dependencies = [];
        for (var i = 0; i < bundle.dependencies.length; i++) {
          var dependency = exports.resolve(bundle.dependencies[i]);
          dependencies.push(dependency);
        };
        return Promise.all(dependencies)
          .then(function(resolvedDependencies) {
            resolve(bundle.constructor.apply(bundle.constructor, resolvedDependencies));
          });
      });
    });
  };

  // Only process the resolve queue after we have loaded.
  // This is because we may not have the guarantee that all of our scripts
  // (and thus types) have been loaded yet, so some scripts loaded in the incorrect
  // order may depend on other scripts that are not loaded yet.
  window.addEventListener('load', function() {
    for (var i = 0; i < resolveQueue.length; i++) {
      resolveQueue[i]();
    };
  });
})(window, Promise, window.inject = window.inject || {});