This is a direct product library.  Examples are shown in lib/product.rb. 
Try:

  % ruby lib/product.rb

To install, execute:

  % ruby install.rb

This is copyrighted free software by GOTO Kentaro <gotoken@notwork.org>.  
You can redistribute it and/or modify it under the terms of the Ruby's
license: http://www.ruby-lang.org/en/LICENSE.rb

$kNotwork: README,v 1.1.1.1 2002/07/05 16:47:00 gotoken Exp $