We try to keep our books accurate, but sometimes mistakes creep in. This page lists the errors submitted by our astute readers. If you've found a new error, please submit it.

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 upgrade it to this version (for free), visit your home page.

Key: Typo Tech. Error Suggestion Not a problem Next edition

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(To find out what version you have, look at the copyright page, a few pages in from the front of the book. If it says (say) 'Second Printing', then here it'll be P2.0. If there are interim PDF releases in that printing, they'll be 2.1, 2.2, and so on.)

PDF Paper Description Found in Fixed in
8
#77057: Hash#slice method includes nil values - trying to implement the ordering by creation_date I've noticed that the update would actually delete p...more...
 P1.0
26-Jul-14
16 2

#76971: We’ll starting building our example application ...

should read

We’ll start building our example application ...--Nathan Egge

 P1.0
08-Jul-14
20
#76413: In the bookmark_list.slim template, bookmark links read: a<> href="bookmark.url" Because of the double quotes, the variable is not interpola...more...
 P1.0
15-Feb-14
46

#77144: The URI to open the example is /example/base - as the sinatra app adds the /example part to it.--Béla

 P1.0
06-Aug-14
57

#76450: Formatting issue.

In the "Do" list of the "Day 2 Self-Study" section, the third bullet is in the middle of a sentence and shouldn't be there.--Alex Marandon

 P1.0
24-Feb-14
131

#76343: It's spelled "hierarchy", not "heirarchy".--Michiel de Mare

 P1.0
27-Jan-14
140

#77059: Program listing: should (def app (-> app-routes ...)) not be (def app (-> all-routes ...)) to combine API- and app- routes?--R. Gabriel Esteves

 P1.0
27-Jul-14
272
#76813: Currently, using inline `REFERENCES` for foreign key definitions is a `bug` (they have it classified as a feature request) in MySQL. I'm r...more...
 P1.0
22-May-14