code: public static function get($interface, $sourceFile)
      {
          if (!isset(self::$_metas[$sourceFile->id])) {
              self::$_metas[$sourceFile->id] = new static($interface, $sourceFile);
          }
  
          return self::$_metas[$sourceFile->id];
      }
docs: Get.
  
  @param InterfaceItem  $interface  the interface object
  @param Source $sourceFile the source file
  
  @return Meta the prepared meta object