OptionParser::List#summarize

# File tmp/rubies/ruby-3.0.5/lib/optparse.rb, line 887
def summarize(*args, &block)
  sum = []
  list.reverse_each do |opt|
    if opt.respond_to?(:summarize) # perhaps OptionParser::Switch
      s = []
      opt.summarize(*args) {|l| s << l}
      sum.concat(s.reverse)
    elsif !opt or opt.empty?
      sum << ""
    elsif opt.respond_to?(:each_line)
      sum.concat([*opt.each_line].reverse)
    else
      sum.concat([*opt.each].reverse)
    end
  end
  sum.reverse_each(&block)
end