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
3
#49968: I typed in the code for db_backup_initial.rb. Your instructions say to run it like this: db_backup_initial.rb # => creates big_client_20110...more...
P1.0
21-Oct-12
4
#49963: Hi. "On UNIX systems, this is done via the first line of code, commonly referred to as the shebang. The shebang starts with a number sign (...more...
P1.0
19-Oct-12
20
#49980: Link to rdoc for OptionParser at the bottom of the page has changed to: ruby-doc.org/stdlib-1.9.3/libdoc/optparse/rdoc/OptionParser.html#metho...more...
P1.0
23-Oct-12
20/36

#49982: The URL to the documentation of OptionParser#make_switch leads to a 404.
--Aljoscha Marcel Everding

P1.0
23-Oct-12
21
#48620: As currently foratted the following two items can be confusing. the '--blah' version has the dashes split across a line break which is a littl...more...
B5.0
31-Jan-12
22
#49981: Re the sample file media.pragprog.com/titles/dccar/code/be_easy_to_use/db_backup/bin/db_backup.rb The sample file contains all three versions...more...
David Copeland says: There is not a straightforward way to provide a better error message. Your options are to include instructive text in the help text or to catch the error raised by OptionParser and do something else. I would agree that neither of these are ideal.
P1.0
23-Oct-12
26
#48980: The command 'gli scaffold to-do new list done' should read 'gli scaffold todo new list done'. If the command is entered as is, you see errors ...more...
P1.0
25-Mar-12
26
#50140: Not really a great nuisance, but it seems to me that it's hard to make this work on my system with a dash in the command name: (00:10:46) j...more...
P1.0
06-Nov-12
26

#48636: `gli scaffold to-do new list done` creates a to-do directory but the given example output and further example commands are sans hyphen.--Larry Marburger

B6.0
02-Feb-12
27

#49984: davetron5000.github.com/gli/classes/GLI.html leads to 404--Aljoscha Marcel Everding

P1.0
23-Oct-12
35

#48960: First paragraph underneath the code example: "That's all there is too it..."--Misty De Meo

P1.0
19-Mar-12
36

#50985: An easier approach is:

opts.banner += " database_name"

David Copeland says: I prefer to have it explicit as to what we are setting the banner to
P1.0
08-Mar-13
41
#50627: In both the source code and the book, the line for the global option filename should be `flag [:f,:filename]` instead of just `flag :f` The...more...
P1.0
31-Jan-13
41
#48637: I don't see where the documentation for the global -f flag is added. Back on page 28 the flag itself is added to the todo app and then on page...more...
B6.0
02-Feb-12
45

#50986: Type on the first line:

"My default..." should read "By default..."

P1.0
08-Mar-13
45
#49112: In doc-sample be_helpful/db_backup/man/db_backup.1.ronn, under section "## DESCRIPTION", second paragraph (top of page 45): "My default, `db_...more...
P1.0
14-Apr-12
57
#48961: "Are there any standard error codeS?" sidebar - MacOS X, based as it is on FreeBSD, also includes the sysexits recommendations. Might be usefu...more...
P1.0
19-Mar-12
58

#49518: if $?.exitstatus & 0b0002

Shouldn't that be: 0b0010 ?
--Eyðun Nielsen

P1.0
13-Jul-12
59
#48661: I'm writing a command line test wrapper that runs a test suite, does some other things and eventually needed to return the status of the tests...more...
B6.0
05-Feb-12
66
#49096: On the example of Format Output One Record per Line, Delimiting Fields: $ todo list 1,Clean kitchen,2011-06-03 13:45, 2,Rake leaves,2011-06...more...
P1.0
11-Apr-12
67

#50755: Last paragraph: "but there's a usability concern here" should be "but there's an usability concern here"--Leonel Santos

P1.0
06-Feb-13
73

#48968: First paragraph doesn't have a close parentheses. (See beginning of paragraph on previous page.)--Misty De Meo

P1.0
20-Mar-12
73

#50784: First paragraph "cronto" should be "cron to"

"The second line tells cronto run our" should be "The second line tells cron to run our" --Leonel Santos

P1.0
11-Feb-13
80
#49113: (Beneath the sidebar "ARGF:...", first paragraph: Missing period after "...standard input to the app)" before start of next sentence "In Ruby,...more...
P1.0
14-Apr-12
114
#49114: First sentence, first paragraph (after code example): "You can then view the RDoc be opening..." should read "You can then view the RDoc by op...more...
P1.0
14-Apr-12
114
#49115: Last paragraph, second-to-last sentence: "This is a great alternative to hosing it yourself,..." should read "This is a great alternative to h...more...
P1.0
14-Apr-12
121

#48948: Code listings don't show the needed require 'aruba/cucumber' in env.rb--David Copeland

P1.0
15-Mar-12
144

#49151: 2nd paragraph from bottom. "An alterantive...", should be "alternative".--Aaron Renner

P1.0
19-Apr-12
165

#51253: "it allows you to execute arbitrary Ruby code, one command
and a time."

Should read "...at a time".

P1.0
08-Apr-13