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The latest version of the book is P3.0, released over 5 years ago. If you've bought a PDF of the book and would like to update 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 (29-Nov-13)
PDF page: 1
This is a bug with the web page for the book, not the book itself. On the Details page on PragProg it says "Q&A with Clay Allsopp, author of RubyMotio...more...
  • Reported in: P3.0 (06-Oct-14)
PDF page: 3

First sentence after code snippet: "The first line specifies the the file encoding..." contains duplicate 'the's--Tyler Karuzis

  • Reported in: P1.0 (07-Jan-13)
PDF page: 27
The filename above the code examples does not match what it would be if you are following along. For example, in Chapter 2, in section 2.3, the filen...more...
  • Reported in: P3.0 (06-Oct-14)
PDF page: 37

First line:

"This present a few problems"

should be 'This presents a few problems'
--Tyler Karuzis

  • Reported in: P1.0 (23-Jun-14)
PDF page: 46

a popular RubyGem called BubbleWrap that “wraps” many

That link is dead

--Bert Mcguirk

  • Reported in: P3.0 (07-Oct-14)
PDF page: 86

First line of second paragraph:
"Now that we have some our UI set up"
is not grammatically correct.
--Tyler Karuzis