This book describes the boost MPL library. Its a very useful guide to this library and it includes enough examples to walk you through how to use it.Secondly the book explains Meta-programming. This is a new concept to a lot of C++ programmers and old hat to LISP programmers. The C++ pre-compiler is constrained to integral types as constraints. But there are a host of tricks you can use within that constraint to build libraries that adapt to their calling structure. Thus generating code that is as efficient as hand written. Of course with your compiler, your milage may vary.The other great thing about using this library, MPL, is that where you would write repeticious template code for every parameter in a template'd library like Tuples, you can automate with it with MPL.Meta programming is a pretty new concept within the C++ community and this book will give us a common language to talk about it. There are other resources on the net, but this book pulls them together.Highly recommended for expert C++ programmers, C++ Library writers and intermediate programmers study'ing to become experts. If you finished Andrei's book, "Modern C++ Design", this is a great next book to buy and own.