think\Route::rules PHP Method

    public static function rules($rules = '')
    {
        if (is_array($rules)) {
            self::$rules = $rules;
        } elseif ($rules) {
            return true === $rules ? self::$rules : self::$rules[$rules];
        } else {
            $rules = self::$rules;
            unset($rules['pattern'], $rules['alias'], $rules['domain'], $rules['name']);
            return $rules;
        }
    }

 protected function buildRouteCache()
 {
     $files = \think\Config::get('route_config_file');
     foreach ($files as $file) {
         if (is_file(CONF_PATH . $file . CONF_EXT)) {
             $config = (include CONF_PATH . $file . CONF_EXT);
             if (is_array($config)) {
                 \think\Route::import($config);
             }
         }
     }
     $rules = \think\Route::rules(true);
     array_walk_recursive($rules, [$this, 'buildClosure']);
     $content = '<?php ' . PHP_EOL . 'return ';
     $content .= var_export($rules, true) . ';';
     $content = str_replace(['\'[__start__', '__end__]\''], '', stripcslashes($content));
     return $content;
 }