I'm guessing he had in mind this (very controversial) feature that was proposed for Ruby 2.0 and then scaled back: http://www.rubyinside.com/ruby-refinements-an

I'm guessing he had in mind this (very controversial) feature that was proposed for Ruby 2.0 and then scaled back: http://www.rubyinside.com/ruby-refinements-an-overview-of-a-new-proposed-ruby-feature-3978.html http://www.rubyinside.com/ruby-refinements-an-overview-of-a-....