# File lib/kwartz/converter.rb, line 353
    def expand_attr_vars(code, attr_info)
      new_code = code.gsub(/\$\((\w+(?::\w+)?)\)/) do |m|
        aname = $1
        #unless attrs.key?(aname)
        #  raise "#{m}: attribute '#{aname}' expected but not found."
        #end
        avalue = attr_info[aname]
        if avalue.is_a?(NativeExpression)
          raise "#{m}: attribute value of '#{aname}' is NativeExpression object."
        end
        avalue
      end
      return new_code
    end