From: "Peña, Botp" <botp@...>
Date: 2005-04-05T15:54:26+09:00
Subject: optparse to include no opt-args, invalid opt,...

Hi,

OptParse is great to use and its opt#on is neatly structured.
I have not perused the internals of optparse and have just taken a look at
the supposedly complete example under optparse. 

i have quick qs though:

1. Can optparse capture nil/empty args?

eg.

C:\family\ruby\optparse>op

C:\family\ruby\optparse>

Of course i can capture empty args. What i want is to include the capture in
optparse structure; something like:

  ....
  opts = OptionParser.new do |opts|
    opts.banner = "Usage: example.rb [options]"

    opts.separator ""
    opts.separator "Specific options:"

    # just empty, no options/arguments.
    opts.Empty_ARG do
      # do something here
      #  <== btw, i'd like to display the banner above here, how?
    end
  .....


2. Can optparse capture a simple arg?

eg.

C:\family\ruby\optparse>op sampleFile

C:\family\ruby\optparse>

Of course we can capture single/simple arguments but again, what i want is
to include it in optparse structure; something like:

  ....
    # just an argument, no option here.
    opts.simple_ARG do |xarg|  #pass the arg
      # do something here
      # maybe i default it to an option like 
      # -f xarg
    end
  .....


3. Can optparse capture errors like invalid options or invalid arguments?

eg.

C:\family\ruby\optparse>op -Z nosuchZoption

C:\family\ruby\optparse>op --delay abc

I can capture errors thru rescue but again, what i want is to include it in
optparse structure; something like:

  ....
    opts.Error do |x|  # pass the error here
	case x
           when OptionParser::InvalidOption
                #....
           when OptionParser::InvalidArgument
                #.....
      else
	end #case
      #exit
    end #opts
  .....


That is all for now.
Thanks to optparse authors/documentor Nobu and Gavin.

thanks and kind regards -botp

btw, s/want/wish/gi. sometimes, my english too harsh.