-- This module implements [[Template:Purge]].  local p = {}  local function makeUrlLink(url, display)  return string.format('[%s %s]', url, display) end  function p._main(args)  -- Make the URL  local url  do  local title  if args.page then  title = mw.title.new(args.page)  if not title then  error(string.format(  "'%s' is not a valid page name",  args.page  ), 2)  end  else  title = mw.title.getCurrentTitle()  end  if args.anchor then  title.fragment = args.anchor  end  url = title:fullUrl{action = 'purge'}  end   -- Make the display  local display  if args.page then  display = args[1] or 'Purge'  else  display = mw.html.create('span')  display  :attr('title', 'Purge this page')  :wikitext(args[1] or 'Purge')  display = tostring(display)  end   -- Output the HTML  local root = mw.html.create('span')  root  :addClass('noprint')  :addClass('plainlinks')  :addClass('purgelink')  :wikitext(makeUrlLink(url, display))   return tostring(root) end  function p.main(frame)  local args = frame:getParent().args  return p._main(args) end  return p