hadley
First edition of online book does not correctly link to second edition
I ran across a link today on stackoverflow that linked to an old version of the book at http://adv-r.had.co.nz/
The top of the page says
You’re reading the first edition of Advanced R; for the latest version see the second edition.
However, the link to the second edition is http://adv-r.had.co.nz/Introduction.html which is still the same website. I think the link needs to be upadted to https://adv-r.hadley.nz/
Seems that Google is also still serving links from the first edition. The very first Google search result for me for "r refclasses" takes me to http://adv-r.had.co.nz/R5.html - which is the old book, and there's no mention on that page that this is the old book (I only realized because I noticed the non secure URL)
