class Kramdown::Converter::Kramdown

def convert_a(el, opts)
  if el.attr['href'].empty?
    "[#{inner(el, opts)}]()"
  elsif el.attr['href'] =~ /^(?:http|ftp)/ || el.attr['href'].count("()") > 0
    index = if link_el = @linkrefs.find {|c| c.attr['href'] == el.attr['href']}
              @linkrefs.index(link_el) + 1
            else
              @linkrefs << el
              @linkrefs.size
            end
    "[#{inner(el, opts)}][#{index}]"
  else
    title = parse_title(el.attr['title'])
    "[#{inner(el, opts)}](#{el.attr['href']}#{title})"
  end
end