small medium large xlarge

The latest version of the book is P3.0, released about 1 year ago. If you've bought a PDF of the book and would like to upgrade it to this version (for free), visit your home page.

By default this page displays the errata for the latest version of the book. If you have a previous version, select it here:

If you've found a new error, please submit it.

  • Typo
  • Tech. error
  • Suggestion
  • Maybe next edition
  • Not a problem
  • Reported in: P1.0 (11-Oct-17)
PDF page: ¨82
In the Safari Books Online edition (no page numbers available), Chapter 3, Quiz: Bug Hunt, the sample output is: 5...​  6... ​  10... ​  Bob go...more...
Paolo Perrotta says: I cannot believe nobody spotted this so far. Thank you! If we have another printing, I will fix it.
  • Reported in: P3.0 (18-Jun-17)
PDF page: 193
The writer is describing the "save_with_validation!" and mistakenly reuse the name again when what he meant was "save_without_validation!". This is ...more...
Paolo Perrotta says: Thanks, Bolatan! I'll submit this for the next printings, if we get any more.