code: protected function parse($response, $depth = 0)
      {
          $page = $this->buildPage($response);
          if ($this->ignore_frames || ! $page->hasFrames() || ($depth > $this->maximum_nested_frames)) {
              return $page;
          }
          $frameset = new SimpleFrameset($page);
          foreach ($page->getFrameset() as $key => $url) {
              $frame = $this->fetch($url, new SimpleGetEncoding(), $depth + 1);
              $frameset->addFrame($frame, $key);
          }
  
          return $frameset;
      }
docs: Parses the raw content into a page.
  Will load further frame pages unless frames are disabled.
  
  @param SimpleHttpResponse $response    Response from fetch.
  @param int $depth                  Nested frameset depth.
  
  @return SimplePage                     Parsed HTML.