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The latest version of the book is B9.0, released 29 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.

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  • Typo
  • Tech. error
  • Suggestion
  • Maybe next edition
  • Not a problem
  • Reported in: B9.0 (22-Aug-19)
#85716
PDF page: 25
Paper page: 44
On second paragraph, "UndefinedFunctionError" is spelled missing a c: "UndefiniedFuntionError". Full text: Before moving forward, let’s briefly revie...more...
  • Reported in: B8.0 (24-Jul-19)
#85605
Paper page: 34
The application.ex file is listed as lib/rumbl/application.ex, but it should be lib/hello/application.ex (the example project rumble is introduced in ...more...
  • Reported in: B9.0 (18-Aug-19)
#85701
PDF page: 80
This code snippet is missing an alias: iex> recompile() iex> alias Rumbl.Repo iex> for u <- Repo.all(User) do ...> Repo.update!(User.registratio...more...
  • Reported in: B9.0 (04-Aug-19)
#85655
PDF page: 92
Paper page: 74
The changeset function sets username AND name as required. In the example, the changeset is changeset = User.changeset(%User{username: "eric"}, %{}...more...
  • Reported in: B9.0 (07-Aug-19)
#85659
PDF page: 188
On p.188 (of the PDF) the instruction is to create a param.ex file with a protocol implementation of to_param I followed the instructions verbatim an...more...
  • Reported in: B9.0 (25-Jul-19)
#85613
Paper page: 203
> We extract the video ID useing pattern matching: "videos:" <> video_id will math all topics starting with "videos:" and assign the rest fo the topic...more...
  • Reported in: B9.0 (08-Aug-19)
#85661
PDF page: 203
"and assign the rest fo the topic to the video_id variable" should be: "and assign the rest of the topic to the video_id variable" fo >> of--Nels...more...
  • Reported in: B9.0 (08-Aug-19)
#85662
PDF page: 212
Grammar (missing word) in the following sentence: "If an application needs change in the future, we can revisit this decision." could be: "If an ap...more...
  • Reported in: B9.0 (20-Aug-19)
#85704
PDF page: 217
The first line of the scheduleMessages function uses scheduleTimer instead of schedulerTimer: wrong: clearTimeout(this.scheduleTimer) right: cl...more...
  • Reported in: B9.0 (28-Jul-19)
#85627
PDF page: 223
channels spelled chanenls when specifying file: lib/rumbl_web/chanenls/video_channel.ex should be lib/rumbl_web/channels/video_channel.ex ...more...
  • Reported in: B9.0 (13-Aug-19)
#85674
PDF page: 239
You instruct the reader "We’re going to need three dependencies, :comeonin, :pbkdf2_elixir and :sweet_xml." whereas the code listing does not contain...more...
  • Reported in: B9.0 (13-Aug-19)
#85677
PDF page: 239
expounding on #85674 - also the listing elides jason, which was in the default depset from the generator for me I don't believe we do any direct js...more...
  • Reported in: B9.0 (31-Jul-19)
#85641
Paper page: 240
In the Copying the Web Source Files section, users need to add RumblWeb.Presence to the list of supervised children and make some changes to RumblWeb....more...
  • Reported in: B9.0 (09-Aug-19)
#85668
PDF page: 241
On page 241 we are advised to move the rumbl/assets/js to rumbl_umbrella/apps/rumbl_web/assets/ That's fine, but then people also need to update the ...more...
  • Reported in: B9.0 (13-Aug-19)
#85675
PDF page: 241
there is no instruction to copy the css over; the styles we added before (video.css from pp 184-185) are minimal but they do exist so its weird to dis...more...
  • Reported in: B9.0 (13-Aug-19)
#85676
PDF page: 242
When adding back the test speed-up config you have the listing as: config :pbkdf2_elixir, :rounds, 1 whereas before it was config :pbkdf2_eli...more...
  • Reported in: B9.0 (10-Aug-19)
#85670
PDF page: 265
While following the OTP chapter, after painstakingly inputting the code for info_sys/lib/info_sys/cache.change1.ex When attempting to follow the i...more...
  • Reported in: B9.0 (10-Aug-19)
#85671
PDF page: 265
Please ignore/delete errata report #85670 I missed the step of adding InfoSys.Cache to Children list in application.ex git<dot>io/fj7XA Cache.put...more...
  • Reported in: B9.0 (30-Jul-19)
#85639
Paper page: 267

In the second paragraph it says there is a :url field on the result struct but that was not included on the previous page.--Sam McDavid

  • Reported in: B9.0 (30-Jul-19)
#85640
Paper page: 269

Application.fetch_env!(:rumbl, :wolfram)[:app_id] on line 39 of the code sample should be :info_sys instead of :rumbl--Sam McDavid

  • Reported in: B9.0 (31-Jul-19)
#85642
Paper page: 295
the mix test command at the bottom of the page intermittently produces an error: mix test test/rumbl_web/channels/video_channel_test.exs . Fini...more...
  • Reported in: B9.0 (11-Aug-19)
#85673
PDF page: 295
Seconding Sam's report #85642, when attempting to run the test: mix test apps/rumbl_web/test/rumbl_web/channels/video_channel_test.exs Getting t...more...
  • Reported in: B9.0 (01-Aug-19)
#85649
Paper page: 391
While following along with chapter 12 I tried to test the information services annotation creation but got an error on Presence: "ArgumentError: :ets....more...