Compare 2 equal-length version numbers in Ruby

version_number_compare.rb

class VersionNumber
  include Comparable
  attr_reader :version_parts

  def initialize version_string
    @version_parts = version_string.split(/[a-zA-Z]/).first.split('.').map(&:to_i)
  end

  def <=> other
    @version_parts.each_with_index do |version_part, i|
      if (comparison = version_part <=> other.version_parts[i]) != 0
        return comparison
      end
    end
    return 0
  end
end


puts "works!" if VersionNumber.new('4.2.12') < VersionNumber.new('4.2.123r13')