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The latest version of the book is P1.0, released 14 days ago. If you've bought a PDF of the book and would like to update it to this version (for free), visit your home page.

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

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  • Typo
  • Tech. error
  • Suggestion
  • Maybe next edition
  • Not a problem
  • Reported in: B4.0 (19-Jan-19)
PDF page: 7

It looks like the generated PDF includes not merged conflict from the book source.--Vladislav Zarakovsky

  • Reported in: P1.0 (18-Feb-19)
PDF page: 51
Paper page: 36
The note for rubyists mentions that property is equivalent to attr_accessor, but we don't see property used until page 57. It might be better to use p...more...
  • Reported in: P1.0 (15-Feb-19)
PDF page: 210
PDF page 210 " Your turn 6 a. b. " I was looking for the answer of the 'Your turn 6 exercise' but "the sample code" that I ...more...