anchor.diff:              - if (user)
                 li
                   a(href='/explore') タグ一覧
  -              li
  -                a(href='/signout') ログアウト
  +              li.dropdown(data-dropdown='dropdown')
  +                a(href='#', class='dropdown-toggle') メニュー
  +                ul.dropdown-menu
  +                  li
  +                    a(href='/about') このサイトについて
  +                  li.divider
  +                  li
  +                    a(href='/signout') ログアウト
               - else
                 li
                   a(href='/signup') ユーザ登録
  
positive.code:     meta(charset='UTF-8')
      title= title
      link(rel='shortcut icon', href='/favicon.png')
      link(rel='stylesheet', href='http://twitter.github.com/bootstrap/1.3.0/bootstrap.min.css')
      link(rel='stylesheet/less', type='text/css', href='/stylesheets/less/base.less')
      script(src='http://cdnjs.cloudflare.com/ajax/libs/less.js/1.1.3/less-1.1.3.min.js')
    body
  
negative.code:     script(src='/javascripts/vendor/jquery.timeago.js')
      script(src='http://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.1.7/underscore-min.js')
      script(src='http://cdnjs.cloudflare.com/ajax/libs/backbone.js/0.5.3/backbone-min.js')
      script(src='http://twitter.github.com/bootstrap/1.4.0/bootstrap-dropdown.js')
      script(src='/javascripts/vendor/socket.io.min.js')
      script(src='/javascripts/vendor/require.js', data-main='/javascripts/application')
  