code: public function addBlank()
      {
          $matched = Preg::match('/^([ \t]*\*)[^\r\n]*(\r?\n)$/', $this->content, $matches);
  
          if (1 !== $matched) {
              return;
          }
  
          $this->content .= $matches[1].$matches[2];
      }
docs: Append a blank docblock line to this line's contents.
  
  Note that this method technically brakes the internal state of the
  docblock, but is useful when we need to retain the indexes of lines
  during the execution of an algorithm.