docs: function () {
        var rootURL = this.rootURL;
  
        _emberMetalDebug.assert('rootURL must end with a trailing forward slash e.g. "/app/"', rootURL.charAt(rootURL.length - 1) === '/');
  
        var implementation = detectImplementation({
          location: this.location,
          history: this.history,
          userAgent: this.userAgent,
          rootURL: rootURL,
          documentMode: this.documentMode,
          global: this.global
        });
  
        if (implementation === false) {
          _emberMetalProperty_set.set(this, 'cancelRouterSetup', true);
          implementation = 'none';
        }
  
        var concrete = _containerOwner.getOwner(this).lookup('location:' + implementation);
        _emberMetalProperty_set.set(concrete, 'rootURL', rootURL);
  
        _emberMetalDebug.assert('Could not find location \'' + implementation + '\'.', !!concrete);
  
        _emberMetalProperty_set.set(this, 'concreteImplementation', concrete);
      }