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The latest version of the book is B2.0, released about 1 month 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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If you've found a new error, please submit it.

  • Typo
  • Tech. error
  • Suggestion
  • Maybe next edition
  • Not a problem
  • Reported in: B2.0 (14-Jan-20)
#86255
PDF page: ??
In the "React" chapter "Adding Our First Component" section, it says, “By declaring this interface, we allow TypeScript to do compile-type type checki...more...
  • Reported in: B2.0 (14-Jan-20)
#86256
PDF page: ??
In the "React" chapter "Composing Components" section, it says, “Invoking a component from another component normally involves a JSX call that looks a...more...
  • Reported in: B2.0 (09-Jan-20)
#86240
PDF page: 4
There is a double "the" in the sentence, "A lot of the decisions about program structure in web applications are about how to manage state, by which I...more...
  • Reported in: B2.0 (09-Jan-20)
#86241
PDF page: 5

Missing the word "to" in the sentence, "We also want make the program as easy as possible to understand and change."--Tom

  • Reported in: B2.0 (01-Jan-20)
#86206
PDF page: 11
Paper page: 24

of the dependences -> of the dependencies--Dominique Broeglin

  • Reported in: B2.0 (16-Jan-20)
#86259
PDF page: 14
Says "Specifically, I’ve added the ESLint code cleanup tool and the Prettier code formatter. These help keep my code clean as I write it, but I’ll tal...more...
  • Reported in: B2.0 (16-Jan-20)
#86260
PDF page: 30
Says "We’re leaving the index.js file itself in JavaScript rather than convert- ing it to TypeScript for the moment because changing it requires a Typ...more...
  • Reported in: B2.0 (02-Jan-20)
#86213
PDF page: 54

<span className="button">{
seatNumber}<</span> has an extra "<" before "/span"--Dominique Broeglin

  • Reported in: B2.0 (02-Jan-20)
#86214
PDF page: 58
The code listen for "turbolinks:load" in "document.addEventListener("turbolinks:load",..." but the text in the following sections explains that we lis...more...
  • Reported in: B2.0 (02-Jan-20)
#86215
PDF page: 63

In "This pattern is called called “lifting state" there are 2 "called"--Dominique Broeglin