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

If you've found a new error, please submit it.

  • Typo
  • Tech. error
  • Suggestion
  • Maybe next edition
  • Not a problem
  • Reported in: P1.0 (25-Nov-19)
  • Fixed: 21-Dec-19, awaiting book release
Paper page: x
asset-server will not start 'DEBUG' is not recognized as an internal or external command, operable program or batch file. npm ERR! code ELIFECY...more...
Randall Koutnik says: Hello! This is an error some folks are encountering on Windows systems. Instead of running: npm start instead run node ./bin/www from the same directory.
  • Reported in: P1.0 (24-Apr-19)
  • Fixed: 21-Dec-19, awaiting book release
Paper page: 1
Cant use the server! PS D:\_current tutorial\rkrxjs-code\asset-server> npm -v 6.9.0 PS D:\_current tutorial\rkrxjs-code\asset-server> node -v v1...more...
  • Reported in: P1.0 (13-Dec-18)
PDF page: 10
Off-by-one error in the stopwatch example. The line map(item => (item / 10)), should read map(item => ((item + 1) / 10)), Otherwise the s...more...
  • Reported in: P1.0 (12-Nov-19)
PDF page: 20
The code snippet: “ ​  ​let​ keyUp$ = fromEvent(textbox, ​'keyup'​) ​  .pipe( ​  map(event =>, ​  map(wordString => wor...more...
  • Reported in: P1.0 (13-Dec-18)
PDF page: 37

Where it says 'mosaic.js' it should say 'mosaic.ts'--Jesus Rodriguez

  • Reported in: P1.0 (16-Jan-20)
Paper page: 83

The last sentence on the page "First, go to app.module.html and add ...", app.module.html should be app.component.html.