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 P1.0, released about 7 years 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

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(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
5
#27901: Page 5 illustrates automated testing for the People application Running rake will fail (at least on my setup) as the first record, defined ...more...
P1.0
21-Mar-07
12
#29375: When running 'ruby script/console', I got the following error: ./script/../config/boot.rb:43:Warning: require_gem is obsolete. Use gem ins...more...
P1.0
31-Jul-07
13
#26947: You say this: This is a book about two worlds: the world of Java programming and the world of Rails programming. Whenever worlds collide, ...more...
P4
07-Feb-07
19
#28958: The class TestPrimitives does not compile, because in the method, on line 1.: 0. public void testSomeLegalConversions() { 1. assertEqua...more...
P1.0
08-May-07
20

#26861: Do you plan to add download links like the Agile Web Development w/ Rails book?--Jeff Duska

P4
18-Jan-07
21
#30320: The "Rails App in Fifteen Minutes" section fails badly with Rails 2.0. I discovered the change in database configuration, and was able to cha...more...
P1.0
04-Jan-08
24
#30381: The sample scaffold app "people" doesn't successfully execute tests with a rake command in rails 1.2.6. It generates eight errors as follows:...more...
P1.0
08-Jan-08
30

#41605: Functions that use blocks for iteration tend [to] pass one or two parameters to the block... in 3rd to last paragraph. Thanks.--M. Roxas

P1.0
23-Nov-09
31
#28534: When executing "script/console" the error occurs on macosx 10.4 (maybe should be mentioned how to solve). => Booting WEBrick... /usr/local...more...
P1.0
14-Apr-07
43
#26864: The paragraph in question contrasts Ruby's dynamic typing with Java's static one. The word "also" seems out of place in the phrase "Java also ...more...
P4
20-Jan-07
43

#27639: Book:
irb(main):025:0> "Hello"[1,4]
=> "ello"

Should be:
irb(main):011:0> "Hello"[1-4]
=> 108--Vladimir

P1.0
14-Mar-07
44

#26863: The sentence before 2.4 Collections and Iteration is missing the reference. "See for a few examples", see what?--Jeff Duska

P4
19-Jan-07
58

#27640: Book:
class Person

Should be
class Person end

Note. "end" never appeared in the book for this class--Vladimir

P1.0
14-Mar-07
59

#26952: spelling mistake: You have "responbility" and it should be "responsibility"--Eli

P4
07-Feb-07
61
#26868: The book has: Ruby provides two equivalent methods: == and .eql?. (Why two methods? See .) The reference to the soapox is missing. Also, ...more...
P4
21-Jan-07
62
#26953: The code from code/rails_xt/samples/programmer.rb (dated 11/28/06) doesn't run because it's missing the following at the top of the source cod...more...
P4
07-Feb-07
62

#41606: Unlike Java [source files], Ruby [source files are] not class-oriented--M. Roxas

P1.0
23-Nov-09
73

#27795: assert nil.blank?
fails.--Vladimir

P1.0
16-Mar-07
73

#27796: Method blank? definition
instead of
empty? || strip.empty?

strip.empty?
does the same job.--Vladimir

P1.0
16-Mar-07
74

#27025: "function" has 8 letters rather than 7 (if that is the "seven letter f-word" mentioned).

P1.0
23-Feb-07
77
#26876: The classpath in the Java command uses Unix separator character, ":". You may want to mention that Windows version of this command will use ";...more...
P4
23-Jan-07
79
#27951: Tried the 'rake migrate' and rake 'db:migrate' as well, but getting the same error: "Illegal route: the :controller must be specified!" An...more...
P1.0
24-Mar-07
79
#27024: To fix the error listed at #6143, just change the line map.connect 'people/:action/:full_name' to map.connect 'people/:action/:full_nam...more...
P1.0
23-Feb-07
85
#26962: Can you show the Ruby classes so that one can compare these to the Java classes shown on previous page? This would help to see the difference...more...
P4
08-Feb-07
86

#26963: How about showing a simple example of duck typing. Theory is nice but concrete examples really help.--El

P4
08-Feb-07
95
#26896: When running the rake command using Rail 1.2.1 you get the following message: Illegal route: the :controller must be specified! (ArgumentErro...more...
P4
29-Jan-07
98

#27008: The rake task migrate has been deprecated. Should be "rake db:migrate".--Gerry Power

P4
20-Feb-07
98
#27783: I am still having problems with the rake migrate. I added to map.connect 'people/:action/:full_name', :controller=>'people' Now it is indic...more...
P1.0
16-Mar-07
101
#26999: You should show somewhere that on InstantRails - in dos command window - one would have to type (after running the InstantRails' use_ruby.cmd ...more...
P1.0
19-Feb-07
105

#26900: In the phrase "it can contain as any number of named parameters", word "as" appears to be superfluous.--Michael Smolyak

P4
29-Jan-07
105

#27005: >>ended< is wrong. It should be:
>>end
--El

P1.0
20-Feb-07
105
#27006: You totally hose up anyone who is trying to follow the example by having them migrate schema to version 0 so tables are wiped, then having the...more...
P1.0
20-Feb-07
118

#41607: Line numbers helpful here, similar to the lines numbers shown on p.102. Thanks.--M. Roxas

P1.0
23-Nov-09
135
#29261: The download link does not work. Also, the routing code on page 135 DOES NOT CONTAIN the code that is described in the surrounding text. T...more...
P1.0
25-Jun-07
144

#26927: hERE IS A Filter--Michael Smolyak

P4
01-Feb-07
146

#26930: I do not suppose you meant "nothing" in the sentence "It is worth nothing that servlet filters...".--Michael Smolyak

P4
02-Feb-07
154
#29418: Ruby on Rails layout templates are .rhtml files, not html. Therefore: ... a template named app/views/layouts/foo.html should be changed t...more...
P1.0
16-Aug-07
167

#26935: I would expect the sample at the bottom of the page to refer to the <bfl> tag created above. There is no such reference, however.--Michael Smolyak

P4
05-Feb-07
168
#29900: There are some syntax errors in the following two files: code/rails_xt/app/views/layouts/quips.rhtml code/rails_xt/app/views/quips/list.rh...more...
P1.0
18-Nov-07
169

#30653: hello.jsp: request.name should be param.name. I don't believe request.name works.--Matt Raible

P1.0
31-Jan-08
178

#26936: Repeated "an" in "When Rails first renders an an action that is page cached".--Michael Smolyak

P4
05-Feb-07
178

#26937: It should probably be "at all" in "Subsequent requests for the page do not encounter Rails as all".--Michael Smolyak

P4
05-Feb-07
189
#26940: This sentence needs to be corrected: "Rails then generates JavaScript to replaces the contents of each DOM id with the result of rendering the...more...
P4
06-Feb-07
245

#26976: Use "are" not "is" in
"The standardized CRUD interfaces is friendly to caches and layered systems."--Michael Smolyak

P4
11-Feb-07
252

#28609: In the irb listing is an &gt; instead of > (I hope this doesn't get messed up when I submit it..)--Mirko Stocker

P1.0
16-Apr-07
304

#26990: Appendix with postgresql(account and password) setup.--Jos

P1.0
15-Feb-07