# Lost with OptionParser **URL:** \ **Category:** Ruby\ **Created:** [July 3, 2008, 2:57am UTC](https://www.ruby-forum.com/t/lost-with-optionparser/142061 "2008-07-03T02:57:37Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![S-gw](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/ed655f/32.png) [@S-gw](https://www.ruby-forum.com/u/S-gw)\ **Post date:** [July 3, 2008, 2:57am UTC](https://www.ruby-forum.com/t/lost-with-optionparser/142061/1 "2008-07-03T02:57:37Z")
I’m having a real problem understanding OptionParser – the docs in pickaxe are rather cryptic, Ruby Way doesn’t even talk about it, and all the Q&A I can find on the web doesn’t clear it up for me. I’ve gotten this far: # test.rb --------- require ‘optparse’ commands = OptionParser.new commands.on("-h", “–help”) # more or less, I get the .on stuff commands.on("-e=RUN\_ENV") commands.parse(ARGV) puts commands # --------- That will dump a display of the commands, but for the life of me, I can’t figure out how to determine which options were actually submitted. And if the -e param was supplied, what’s its value is. I have seen: commands.parse(ARGV) commands.parse!(ARGV) options = commands.parse(ARGV) So, confused by that to start with, then really confused by where the parsed commands are, and what format they’re in. – gw ---
**Author:** ![S-gw](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/ed655f/32.png) [@S-gw](https://www.ruby-forum.com/u/S-gw)\ **Post date:** [July 3, 2008, 5:07am UTC](https://www.ruby-forum.com/t/lost-with-optionparser/142061/2 "2008-07-03T05:07:04Z")
Here is a quick example program. Hope this gets you started. #!/usr/bin/env ruby require ‘optparse’ options = {} opts = OptionParser.new opts.on("-W", “–weekday”, “Print out the weekday”) do |v| options[:weekday] = true end opts.on("-H", “–hour TYPE”, “Print out the hour in 24 or 12 hour clock”) do |v| options[:hour] = v end opts.parse! unless options[:weekday] || options[:hour] puts opts exit end if options[:weekday] puts Time.now.strftime("%A") exit end case options[:hour] when “12” puts Time.now.strftime("%I") when “24” puts Time.now.strftime("%H") else puts “You must send 12 or 24 as an argument to --hour” end ---
**Author:** ![S-gw](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/ed655f/32.png) [@S-gw](https://www.ruby-forum.com/u/S-gw)\ **Post date:** [July 3, 2008, 5:51am UTC](https://www.ruby-forum.com/t/lost-with-optionparser/142061/3 "2008-07-03T05:51:25Z")
dusty wrote: > Here is a quick example program. Hope this gets you started. Yes! That turned out to be the Rosetta Stone to help me interpret and fill the gaps in the other examples I’ve found. Many thanks. – gw ---
**Author:** ![S-gw](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/ed655f/32.png) [@S-gw](https://www.ruby-forum.com/u/S-gw)\ **Post date:** [July 3, 2008, 7:27pm UTC](https://www.ruby-forum.com/t/lost-with-optionparser/142061/4 "2008-07-03T19:27:21Z")
I love Main, but it does not seem to work under JRuby, any ideas? This is the error I always get… F, [2008-07-03T10:24:48.827600 #9761] FATAL – : could not reopen: null (IOError) /opt/jruby-1.1.2/lib/ruby/gems/1.8/gems/main-2.8.0/lib/main/base.rb:318:in `setup_io_restoration' /opt/jruby-1.1.2/lib/ruby/gems/1.8/gems/main-2.8.0/lib/main/base.rb:318:in`call’ /opt/jruby-1.1.2/lib/ruby/gems/1.8/gems/main-2.8.0/lib/main/base.rb:318:in `finalize' /opt/jruby-1.1.2/lib/ruby/gems/1.8/gems/main-2.8.0/lib/main/base.rb:29:in`run’ /opt/jruby-1.1.2/lib/ruby/gems/1.8/gems/main-2.8.0/lib/main/base.rb:12:in `catch' /opt/jruby-1.1.2/lib/ruby/gems/1.8/gems/main-2.8.0/lib/main/base.rb:12:in`run’ /opt/jruby-1.1.2/lib/ruby/gems/1.8/gems/main-2.8.0/lib/main/factories.rb:11:in `run' /opt/jruby-1.1.2/lib/ruby/gems/1.8/gems/main-2.8.0/lib/main/factories.rb:16:in`Main’ ---
**Author:** ![S-gw](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/ed655f/32.png) [@S-gw](https://www.ruby-forum.com/u/S-gw)\ **Post date:** [July 3, 2008, 7:33pm UTC](https://www.ruby-forum.com/t/lost-with-optionparser/142061/5 "2008-07-03T19:33:48Z")
On Jul 3, 2008, at 11:22 AM, Jim M. wrote: > /opt/jruby-1.1.2/lib/ruby/gems/1.8/gems/main-2.8.0/lib/main/base.rb: > factories.rb:16:in `Main’ > it should be able to do - might take some hacking to deal with > different handling of stdout/stderr/stdin. patches welcome! 😉 a @ [http://codeforpeople.com/](http://codeforpeople.com/) ---
**Author:** ![S-gw](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/ed655f/32.png) [@S-gw](https://www.ruby-forum.com/u/S-gw)\ **Post date:** [July 3, 2008, 9:03pm UTC](https://www.ruby-forum.com/t/lost-with-optionparser/142061/6 "2008-07-03T21:03:02Z")
On Jul 3, 12:29 pm, “ara.t.howard” [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > it should be able to do - might take some hacking to deal with > different handling of stdout/stderr/stdin. patches welcome! > > 😉 I’ll consider writing the patches after you write the specs. And by “specs” I mean actual specs, not a load of numbered tests. I was disappointed there was no test\_420, btw. ---
**Author:** ![S-gw](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/ed655f/32.png) [@S-gw](https://www.ruby-forum.com/u/S-gw)\ **Post date:** [July 3, 2008, 6:05am UTC](https://www.ruby-forum.com/t/lost-with-optionparser/142061/7 "2008-07-03T06:05:40Z")
On Jul 2, 2008, at 6:54 PM, Greg W. wrote: > commands = OptionParser.new > can’t figure out how to determine which options were actually > parsed commands are, and what format they’re in. > > ## – gw > > Posted via [http://www.ruby-forum.com/](http://www.ruby-forum.com/). cfp:~ \> cat a.rb require ‘yaml’ require ‘rubygems’ ### gem install rubygems require ‘main’ Main { option(‘environment’, ‘e’){ synopsis ‘specify run time environment’ default ‘development’ argument :required validate{|arg| %w[production development test].include? arg} } def run environment = params[‘environment’] ``` y :given => environment.given?, :value => environment.value ``` end } ## cfp:~ \> ruby a.rb :value: development :given: cfp:~ \> ruby a.rb --environment=foobar invalid: option(–environment)=“foobar” ## cfp:~ \> ruby a.rb --environment=test :value: test :given: true cfp:~ \> ruby a.rb --help NAME a.rb SYNOPSIS a.rb [options]+ DESCRIPTION main.rb takes the pain of argument parsing away PARAMETERS specify run time environment –help, -h the packages ships with a tons of examples. a @ [http://codeforpeople.com/](http://codeforpeople.com/) ---
**Author:** ![S-gw](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/ed655f/32.png) [@S-gw](https://www.ruby-forum.com/u/S-gw)\ **Post date:** [July 3, 2008, 10:05pm UTC](https://www.ruby-forum.com/t/lost-with-optionparser/142061/8 "2008-07-03T22:05:13Z")
On Jul 3, 2008, at 12:59 PM, Yossef M. wrote: > I’ll consider writing the patches after you write the specs. > > And by “specs” I mean actual specs, not a load of numbered tests. I > was disappointed there was no test\_420, btw. heh - well i’ve got about 51 projects on rubyforge attm, nearly all of them pre-dating bacon and co. if anyone wants to help migrate the tests… i’ve got some old perl code that needs ported to ruby too. and a stack of svn projects which need moved to github… 😉 a @ [http://codeforpeople.com/](http://codeforpeople.com/)