# File lib/thor/options.rb, line 161
    def formatted_usage
      return "" if @switches.empty?
      @switches.map do |opt, type|
        case type
        when :boolean
          "[#{opt}]"
        when :required
          opt + "=" + opt.gsub(/\-/, "").upcase
        else
          sample = @defaults[undasherize(opt)]
          sample ||= case type
            when :optional then undasherize(opt).gsub(/\-/, "_").upcase
            when :numeric  then "N"
            end
          "[" + opt + "=" + sample.to_s + "]"
        end
      end.join(" ")
    end