    # File lib/compass/sass_extensions/functions/selectors.rb, line 15
      def nest(*arguments)
        nested = arguments.map{|a| a.value}.inject do |memo,arg|
          ancestors = memo.split(COMMA_SEPARATOR)
          descendants = arg.split(COMMA_SEPARATOR)
          ancestors.map{|a| descendants.map{|d| "#{a} #{d}"}.join(", ")}.join(", ")
        end
        Sass::Script::String.new(nested)
      end