module Mixlib::CLI

def opt_parser
  @opt_parser ||= OptionParser.new do |opts|
    # Set the banner
    opts.banner = banner
    # Create new options
    options.sort { |a, b| a[0].to_s <=> b[0].to_s }.each do |opt_key, opt_val|
      opt_args = build_option_arguments(opt_val)
      opt_method = case opt_val[:on]
                   when :on
                     :on
                   when :tail
                     :on_tail
                   when :head
                     :on_head
                   else
                     raise ArgumentError, "You must pass :on, :tail, or :head to :on"
                   end
      parse_block =
        Proc.new() do |c|
          config[opt_key] = (opt_val[:proc] && opt_val[:proc].call(c)) || c
          puts opts if opt_val[:show_options]
          exit opt_val[:exit] if opt_val[:exit]
        end
      full_opt = [ opt_method ]
      opt_args.inject(full_opt) { |memo, arg| memo << arg; memo }
      full_opt << parse_block
      opts.send(*full_opt)
    end
  end
end