# File lib/rubygame/mediabag.rb, line 83
    def load_file(filename)
      case File::extname(filename).downcase[1..-1]
      when *(@@image_ext)
        return load_image(filename)
      when *(@@sound_ext)
        return load_sound(filename)
      else
        raise(ArgumentError,"Unrecognized file extension `%s': %s"%
              [File::extname(filename), filename])
      end
    end