helper methods to generate mdoc from OptionParser in Ruby

gistfile1.rb

require 'optparse'
class OptionParser
  def list_opts(prior_opts)
    opts = enum_for(:visit, :tap).map(&:list).flatten(1)
    prior_opts = opts.select{|opt| opt.long.any?{|name| prior_opts.include?(name)} }
    opts -= prior_opts

    simple_opts = opts.select{|opt| !opt.short.empty? && opt.arg.nil? }.sort_by{|x| x.short.sort.first}
    opts -= simple_opts

    arg_opts = opts.select{|opt| !opt.short.empty?}.sort_by{|x| x.short.sort.first}
    opts -= arg_opts

    opts = opts.sort{|x,y| x.long.sort.first}

    return prior_opts, simple_opts, arg_opts, opts
  end
  private :list_opts

  def to_mdoc_synopsis(prior_opts)
    prior, simple, arg, long = list_opts(prior_opts)

    synopsis = ".Sh SYNOPSIS¥n.Nm¥n"
    prior.each do |opt|
      synopsis << ".Op Fl " << opt.long.sort.first[1..-1]
      if opt.arg =~ /¥[([^¥]]+)¥]/
        synopsis << " Op Ar " << $1
      elsif opt.arg
        synopsis << " Ar " << opt.arg[/¥S+/]
      end
      synopsis << "¥n"
    end

    synopsis << ".Op Fl " << simple.map{|x| x.short.first[-1, 1]}.join << "¥n"

    (arg + long).each do |opt|
      name = opt.short.sort.first || opt.long.sort.first
      synopsis << ".Op Fl " << name[1..-1]
      if opt.arg =~ /¥[([^¥]]+)¥]/
        synopsis << " Op Ar " << $1
      elsif opt.arg
        synopsis << " Ar " << opt.arg[/¥S+/]
      end
      synopsis << "¥n"
    end

    synopsis.chomp
  end

  def to_mdoc_description(prior_opts)
    prior, simple, arg, long = list_opts(prior_opts)

    synopsis = <<EOS
.Sh OPTIONS
.Bl -tag -width "1234567890123" -compact
.Pp
EOS
    prior.each do |opt|
      synopsis << ".It Fl " << opt.long.sort.first[1..-1]
      if opt.arg =~ /¥[([^¥]]+)¥]/
        synopsis << " Op Ar " << $1
      elsif opt.arg
        synopsis << " Ar " << opt.arg[/¥S+/]
      end
      synopsis << "¥n"
      synopsis << opt.desc.join << "¥n.Pp¥n"
    end

    short = (simple + arg).sort_by{|x| x.short.sort.first}
    (short + long).each do |opt|
      (opt.short.sort + opt.long.sort).each do |name|
        synopsis << ".It Fl " << name[1..-1]
        if opt.arg =~ /¥[([^¥]]+)¥]/
          synopsis << " Op Ar " << $1
        elsif opt.arg
          synopsis << " Ar " << opt.arg[/¥S+/]
        end
        synopsis << "¥n"
      end
      synopsis << opt.desc.join << "¥n.Pp¥n"
    end

    synopsis << <<'EOS'
.El
.Pp
EOS

    synopsis.chomp
  end
end