docs: function (fullName, options) {
        _emberMetalDebug.assert('fullName must be a proper full name', this.validateFullName(fullName));
        var factory = resolve(this, this.normalize(fullName), options);
        if (factory === undefined && this.fallback) {
          var _fallback;
  
          factory = (_fallback = this.fallback).resolve.apply(_fallback, arguments);
        }
        return factory;
      }