# File lib/RMagick.rb, line 1244
    def __map__(&block)
        cfid = self[@scene].__id__ rescue nil
        ensure_image = Proc.new do |img|
            rv = block.call(img)
            is_a_image rv
            return rv
        end
        a = self.class.new.replace __ary_map__(&ensure_image)
        a.set_cf cfid
        return a
    end