We try to keep our books accurate, but sometimes mistakes creep in. This page lists the errors submitted by our astute readers. If you've found a new error, please submit it.

The latest version of the book is P3.0, released 7 months 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.

Key: Typo Tech. Error Suggestion Not a problem Next edition

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

(To find out what version you have, look at the copyright page, a few pages in from the front of the book. If it says (say) 'Second Printing', then here it'll be P2.0. If there are interim PDF releases in that printing, they'll be 2.1, 2.2, and so on.)

PDF Paper Description Found in Fixed in
1
#53228: 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 R...more...
 P1.0
29-Nov-13
3

#77554: First sentence after code snippet: "The first line specifies the the file encoding..." contains duplicate 'the's--Tyler Karuzis

 P3.0
06-Oct-14
27
#50445: 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, t...more...
 P1.0
07-Jan-13
37

#77556: First line:

"This present a few problems"

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

 P3.0
06-Oct-14
46

#76885: a popular RubyGem called BubbleWrap bubblewrap.io that “wraps” many

That link is dead

--Bert Mcguirk

 P1.0
23-Jun-14
86

#77565: First line of second paragraph:
"Now that we have some our UI set up"
is not grammatically correct.
--Tyler Karuzis

 P3.0
07-Oct-14