class Gem::OptionParser::Switch

def compsys(sdone, ldone)   # :nodoc:
  sopts, lopts = [], []
  @short.each {|s| sdone.fetch(s) {sopts << s}; sdone[s] = true} if @short
  @long.each {|s| ldone.fetch(s) {lopts << s}; ldone[s] = true} if @long
  return if sopts.empty? and lopts.empty? # completely hidden
  (sopts+lopts).each do |opt|
    # "(-x -c -r)-l[left justify]"
    if /^--\[no-\](.+)$/ =~ opt
      o = $1
      yield("--#{o}", desc.join(""))
      yield("--no-#{o}", desc.join(""))
    else
      yield("#{opt}", desc.join(""))
    end
  end
end