Parsing flags from a file in Clamp in Ruby

conf

--version 1.2.3.4

output.txt

# Reading flags from the given `--config-file` path should work :)
% ruby test.rb --version 5.5.5.5 --config-file /tmp/conf
Version: 1.2.3.4

test.rb

#!/usr/bin/env ruby
#
require "clamp"
require "shellwords"
require "pry"

class Foo < Clamp::Command

  option "--config-file", "FILE", "Load additional options (flags) from a given file." do |path|
    # Parse the file
    File.read(path).split("\n").each do |line|
      # Parse each line of the file as a "shell" syntax splitting into shell words.
      args = Shellwords.split(line)

      # Process arguments from this line
      while args.any?
        # The steps in this file are based on Clamp's Option::Parsing#handle_switch method.
        arg = args.shift

        # Lookup the flag by its --flag-name
        option = self.class.find_option(arg)

        # Extract the flag value, if any, from the remaining args list.
        value = option.extract_value(arg, args)

        # Process the flag into `self`
        option.of(self).take(value)
      end
    end
  end

  option "--version", "VERSION", "The version", :default => "1.0"

  def execute
    puts "Version: #{version}"
  end
end

Foo.run($0, ARGV)