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The latest version of the book is P1.0, released about 1 month 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.

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  • Typo
  • Tech. error
  • Suggestion
  • Maybe next edition
  • Not a problem
  • Reported in: P1.0 (15-Sep-17)
PDF page: 20
When running "rspec --profile 2" you display the result as "5 examples, 0 failures". But on the previous page (19), we haven't yet fixed the error for...more...
Myron Marston says: Great question! In the "Identifying Slow Examples" section you're referring to, we aren't intending to show what that's like when applied to the coffee example with a failing spec. Rather, we're showing off the --profile feature when running against the slow_spec.rb file shown in that section. That's why it shows "5 examples, 0 failures", since slow_spec.rb has 5 examples and they all pass. I'm glad you pointed this out, though, because it is a bit confusing. We'll plan to address this in the next edition by re-ordering the sections or including a better explanation in the text.
  • Reported in: P1.0 (04-Sep-17)
PDF page: 53
"Ruby’s JSON library can safely parse simple a record like this one into a Ruby hash" "simple" and "a" are in the the wrong order. Should be ...more...
Myron Marston says: Thanks for reporting this! At this point, the book has been printed, so it's unfortunately too late for us to fix this typo. If there's a 2nd edition, we'll plan to include this fix (unless the section is entirely rewritten...).
  • Reported in: P1.0 (28-Sep-17)
Paper page: 128

The phrase "but you can also also add helper" contains double "also".--Serguei Cambour

Myron Marston says: Good catch! We'll be sure to address this in the next edition.
  • Reported in: P1.0 (10-Oct-17)
  • Fixed: 10-Oct-17, awaiting book release
PDF page: 188

... so you’d like to memoize (cache) the result should be

so you’d like to memorize (cache) the result.--Serguei Cambour

Myron Marston says: Actually, our usage of "memoize" (no "r") is intentional. We introduce this term on page 12, with a link to a blog post that explains it more in depth.