From: Milo Thurston <milo.thurston@...01.nerc-oxford.ac.uk>
Date: 2004-05-11T23:23:53+09:00
Subject: GetoptLong order of options

I've just started trying out ruby, having been using perl, and
encountered a small problem with the getopt module, as follows.
I re-wrote a script that is meant to glob huge numbers of files, 
to get around the shell's globbing limitations. It has options
for the suffix to glob "-g" and other things to do e.g. "-d" to
delete them. However, the options work in one order but not another,
e.g.

$ ./globber.rb -g gbk -d 
globs *.gbk and deletes the files.

$ ./globber.rb -d -g gbk 
Fails to glob any files and exits.

Here are the relevant parts of the code.

parser = GetoptLong.new
parser.ordering = GetoptLong::PERMUTE
parser.set_options(
	["-h", "--help", GetoptLong::NO_ARGUMENT],
	["-d", "--delete", GetoptLong::NO_ARGUMENT],
	["-g", "--glob", GetoptLong::REQUIRED_ARGUMENT],
	["-o", "--output", GetoptLong::OPTIONAL_ARGUMENT]
)

# process options
files = nil
outfile = nil
loop do
	begin
		opt, arg = parser.get
		break if not opt
		case opt
			when "-g"
				files = Dir["*.#{arg}"]
			when "-d" 
				files.each {|f|
				File.unlink(f)
				puts "Deleting #{f}..."
			}
			exit
	end
end

if files == nil
	puts "No files available!"
else
	puts files
end


Presumably my problem is the loop, but I can't see any other way to do
this in the documents. Is there an equivalent of perl's use of a hash
to process options?
Thanks for any suggestion.

-- 
Remove surname to reply.
http://www.bioinf.ceh.ac.uk/lab/