[SOLVED] Simple explanation for this optparse example from Ruby

Simple explanation for this optparse example from Ruby

require 'optparse'

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

  opts.on("-v", "--[no-]verbose", "Run verbosely") do |v|
    options[:verbose] = v
  end
end.parse!

p options
p ARGV

I found this from the optparse documentation page here. Can someone please explain this example in layman terms? I read the documentation but, there are some parts I don't understand. Namely, the end.parse! and the difference between the methods parse and permute.

Solution

The end.parse! is not some magical kind of end if that's what you were thinking. It can be written like this:

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

  opts.on("-v", "--[no-]verbose", "Run verbosely") do |v|
    options[:verbose] = v
  end
end

option_parser.parse!