     node.title = s.a[0]._
     node.link = s.a[0].href[0].replace(/\.(md|markdown)$/i, '')
   if s.ul
-    if s.ul[0] && s.ul[0].li
+    if s.ul[0]?.li
       list = s.ul[0].li
-    else if s.ul && s.ul.li
+    else if s.ul?.li
       list = s.ul.li
     node.list = list.map((a) -> summaryParser({}, a))
   node

articleRender = new Renderer()

articleRender.heading = (text, level) ->
  (if level < 2 then '<div class="page-header">' else '')
  + "<h#{level}>#{text}</h#{level}>"
  + (if level < 2 then '</div>' else '')

articleRender.table = (header, body) ->
  '<div class="table-responsive">\

  </div>'

articleRender.link = (href, title, text) ->
  '<a href="' +
  href.replace(/([^\:]+?)(\/?)([^\:]*?)\.(md|markdown)$/, '$1$2$3.html') +
  '"' +
  (if title then ' title="' + title + '"' else '') +
  ">#{text}</a>"

summaryRender.heading = -> ''

