This is the last of a series of free excerpts from an eBook I’m writing called Ruby Under a Microscope. I plan to finish the book and make it available for purchase and download from this web site before RubyConf 2012 on Nov. 1. You can still sign up here, if you haven’t already, to receive an email when the book is finished. I plan send that one, single email message out to everyone before Novemb