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.

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PDF Paper Description Found in Fixed in
38

#46004: The last paragraph on page 38 has two sentences repeated at the top of page 39.

B8.0
14-Dec-10
44

#47901: url.get_protocol # Isn't assigned.

url = URL.new 'http', 'pragprog.com', '/titles' # FIFY--Johnneylee Jack Rollins

P1.0
06-Nov-11
44

#47902: attributes.rb doesn't really make sense to have a code example for, seeing as it's purely for users to digest and not actually run.--Johnneylee Jack Rollins

P1.0
06-Nov-11
58
#46185: Question I had reading this: does the become_java! method described earlier help at all with the "lost monkeypatches" problem? Or does it onl...more...
B8.0
05-Jan-11
64
#47818: Issuing the command `ant`, the `do_compile` step fails due to not finding the jruby embed package. I have issued this before running `ant`,...more...
P1.0
26-Oct-11
68
#47903: Referring to ruby methods as functions and then again as methods is somewhat confusing. I suggest referring to ruby methods as methods and jav...more...
P1.0
06-Nov-11
83

#46413: "and long-running programs well seem" should be "and long-running programs will seem"

--Romain Primet

P1.0
17-Feb-11
106
#46264: There's a much better way to do platform detection for Jruby and regular ruby You can say: platforms :jruby do gem 'activerecord-jdbc-...more...
B8.0
18-Jan-11
109
#45796: I think you are aware of an issue using JRuby 1.5.5 and Rails 3.0.3 but might make mention or make sure the reader is using newer version of J...more...
B7.0
27-Nov-10
126
#46405: When generating the scaffold for Review, the first -- argument should be --migration, not --migrate. If using --migrate, the error at the com...more...
P1.0
15-Feb-11
155
#46408: Building Ribs using the current version of rspec (2.5.0 as it type this), as installed by the previous commands, will fail as the Rakefile ass...more...
P1.0
16-Feb-11
169
#46232: In the first ant example the name of the target ('hello_from_ant') does not correspond with the default target name ('hello'), so calling 'ant...more...
B8.0
13-Jan-11
226
#46195: I have had a great deal of trouble getting JTestR to work for my project. With the config from the book (0.6) I get: [INFO] Internal error...more...
B8.0
06-Jan-11
243
#45843: Last line "Next install the Monkeybars gem..." would read better if it were in a new paragraph. At the moment, this gives the impression it's...more...
B7.0
01-Dec-10
250
#52111: Error installing monkeybars. Book says "jruby -S gem install monkeybars rawr" but neither is found in any repository. Installed rawr like t...more...
P1.0
02-Jul-13
261
#52110: Command to launch limelight demos does not work: book says "jruby -S limelight open" but I haven't been able to figure out what the correct ...more...
P1.0
02-Jul-13