P4.0 (Printing) - 25 June 2013

Fourth printing, updated to Ruby 2.0.

P3.0 (Printing) - 14 October 2011

Third Printing.

This release fixes several errata. For complete details, please see errata.

P2.0 (Printing) - 05 May 2010

  • Second Printing, minor errata fixes

P1.1 - 30 March 2009

Due to a production error in the P1.0 version, some code output contained error messages instead of the actual code output. This problem has been corrected in this version.

P1.0 (Printing) - 25 March 2009

First printing

B1.0 - 21 January 2009