- https://mauricio.github.io/2008/09/27/including-and-extending-modules-in-ruby.html
- https://mauricio.github.io/2009/06/04/understanding-class_eval-module_eval-and-instance_eval.html
- https://mauricio.github.io/2011/05/30/ruby-basics-equality-operators-ruby.html
- http://www.eq8.eu/blogs/13-ruby-ancestors-descendants-and-other-annoying-relatives
Ruby Articles
2017-08-29