class RDoc::Parser::Ruby

def skip_optional_do_after_expression
  skip_tkspace_without_nl
  tk = get_tk
  b_nest = 0
  nest = 0
  loop do
    break unless tk
    case tk[:kind]
    when :on_semicolon, :on_nl, :on_ignored_nl then
      break if b_nest.zero?
    when :on_lparen then
      nest += 1
    when :on_rparen then
      nest -= 1
    when :on_kw then
      case tk[:text]
      when 'begin'
        b_nest += 1
      when 'end'
        b_nest -= 1
      when 'do'
        break if nest.zero?
      end
    when :on_comment, :on_embdoc then
      if b_nest.zero? and "\n" == tk[:text][-1] then
        break
      end
    end
    tk = get_tk
  end
  skip_tkspace_without_nl
  get_tk if peek_tk && :on_kw == peek_tk[:kind] && 'do' == peek_tk[:text]
end