Well, you guessed it, it's not.
The information is scattered across the web on blogs, forums, tweets, etc.
I can bitch about it, or do something about it... I choose the second.
There used to be a website (an old one, from when Haxe spelled "haXe") that got you started.But that website is no more. I decided to get some of that back. This documentation is based upon the information from the old site and my own need to document Haxe. I started with the information from the old site. A simple copy, paste. Most of the content of this site/book is from different sources (with permission of the writers). Eventually (that means in the future) I will rewrite it (or not).
You can find the original data with WayBack Machine