code: public function renderOption(Option $opt)
      {
          $c1 = '';
          if ($opt->short && $opt->long) {
              $c1 = sprintf('-%s, --%s', $opt->short, $opt->long);
          } else if ($opt->short) {
              $c1 = sprintf('-%s', $opt->short);
          } else if ($opt->long) {
              $c1 = sprintf('--%s', $opt->long);
          }
          $c1 .= $opt->renderValueHint();
  
          return $c1;
      }
docs: Render readable spec.