original_string: protected function flush($maxBufferLevel = null)
      {
          if (null === $maxBufferLevel) {
              $maxBufferLevel = ob_get_level();
          }
  
          while (ob_get_level() > $maxBufferLevel) {
              ob_end_flush();
          }
      }
code: protected function flush($maxBufferLevel = null)
      {
          if (null === $maxBufferLevel) {
              $maxBufferLevel = ob_get_level();
          }
  
          while (ob_get_level() > $maxBufferLevel) {
              ob_end_flush();
          }
      }
code_tokens: protected function flush ( $ maxBufferLevel = null ) { if ( null === $ maxBufferLevel ) { $ maxBufferLevel = ob_get_level ( ) ; } while ( ob_get_level ( ) > $ maxBufferLevel ) { ob_end_flush ( ) ; } }
docstring: Loops through the output buffer, flushing each, before emitting
  the response.
  
  @param int|null $maxBufferLevel Flush up to this buffer level.
  @return void
docstring_tokens: Loops through the output buffer flushing each before emitting the response .