# File gtk/sample/gtk-demo/hypertext.rb, line 62
    def insert_link(buffer, iter, text, page)
      tag = buffer.create_tag(nil,
                              {
                                'foreground' => 'blue',
                                'underline' => Pango::AttrUnderline::SINGLE,
                              })
      tag.page = page

      buffer.insert(iter, text, tag)
      print("Insert #{tag}:#{page}\n")
    end