From: Thomas Leitner <t_leitner@...>
Date: 2004-11-04T05:38:46+09:00
Subject: Re: From getoptlong to optparse

On Tue, 02 Nov 2004 20:33:15 GMT
Massimiliano Mirra - bard <mmirra@libero.REMOVETHIS.it> wrote:

| 
| I have a command line program invoked like this:
| 
|   $ prog --host localhost --port 8000 login --password secret
|   $ prog --host localhost --port 8000 list --open
| 
| ...and so on.  In other words:
| 
|   $ command [general options] subcommand [specific options]
| 
| Like darcs or cvs.
| 
| So far I've been doing fine with getoptlong:
| 
|     while ARGV.first =~ /^-/
|       opt, arg = opts.get
|       case opt
|       when "--host"
|         config["host"] = arg
|       when "--port"
|         config["port"] = arg.to_i
|       end
|     end
| 
| When the loop sees the first thing that does not begin with `-'
| (option arguments don't count, they get eaten by opts.get), it assumes
| it to be the subcommand, and leaves ARGV alone from that point on.
| ARGV is later emptied by the subcommand specific options parsing.
| 
| I'd like to migrate to optparse, though.  But how can I stop argument
| parsing at a certain point in optparse?
| 
| Massimiliano

You may want to take a look at cmdparse.rubyforge.org. It is based on optparse, but provides the semantics of subcommands as you called them. Your command line

  $ command [general options] subcommand [specific options]

is a prime example for the use of it. Have a look at the example at this page http://cmdparse.rubyforge.org/rdoc/classes/CommandParser.html

*hth*,
Thomas Leitner