# File lib/nokogiri/xml/document_fragment.rb, line 10
      def initialize document, tags = nil, ctx = nil
        return self unless tags

        children = if ctx
                     ctx.parse(tags)
                   else
                     XML::Document.parse("<root>#{tags}</root>") \
                       .xpath("/root/node()")
                   end
        children.each { |child| child.parent = self }
      end