C++ Templates - The complete guide
One of the numerous benefits that working at Microsoft brings is that you can just walk in one of the internal libraries and find such a book. I've just finished the first hundred pages and although I did not learn much as I know that topic, it was still quite entertaining to read. I can't wait to read the next ~400 pages. One of the authors site is at https://www.josuttis.com/tmplbook/.
One book I'll soon buy as I want it in my library.
(a little bit of history Template metaprogramming and Expression templates inventors...)