# File lib/asciidoctor/document.rb, line 495
  def counter(name, seed = nil)
    if (attr_is_seed = !(attr_val = @attributes[name]).nil_or_empty?) && @counters.key?(name)
      @counters[name] = nextval(attr_val)
    else
      if seed.nil?
        seed = nextval(attr_is_seed ? attr_val : 0)
      elsif seed.to_i.to_s == seed
        seed = seed.to_i
      end
      @counters[name] = seed
    end

    (@attributes[name] = @counters[name])
  end