From: Robert Klemme <bob.news@...>
Date: 2003-07-19T01:05:06+09:00
Subject: Re: Usage Message for GetoptLong


That's a nice coincidence - or a proof for the theory of morphogenetic
fields: I was just today wanting to have the same functionality and
equally thought how nice it would be to simply have an additional string
parameter containing the usage.

Hmmm, let's see...  I'd override set_options instead of initialize because
that is the method douing the work.  Try this:

class GetoptLong
    alias old_set_options set_options

    def set_options(*options)
        @descriptions = []
        @opt_help = "Options:\n"

        options.each do |arg|
            if hasDescription? arg
                @opt_help << sprintf("%-20s: %s\n", arg[0..-3].join( ',
' ), arg.pop )
            else
                @opt_help << arg[0..-2].join( ', ' ) << "\n"
            end
        end

        @opt_help << "\n"

        old_set_options(*options)
    end

    def usage(message="Usage:")
      puts message
      puts @opt_help
    end

    private

    def hasDescription?(optarray)
        case optarray[-1]
          when GetoptLong::REQUIRED_ARGUMENT,
               GetoptLong::NO_ARGUMENT,
               GetoptLong::OPTIONAL_ARGUMENT
            false
          else
            true
        end
    end
end


Regards

    robert