The book Real World Haskell is receiving some amazing reviews on Amazon, with comments like

This by far is one of the best programming books not only on Haskell as the language, but also the fundamentals of pure functional programming in general. This book in my opinion is a game changer to bring Haskell to the forefront of people’s attentions. Whether you’ve been a programmer for years or just starting out, this book fits both needs quite nicely. If only other books could live up to this standard.

The content of the book is available for free online as well. Because of the excellent reviews and a desire to learn some more about functional programming I’ve decided to go through the book and will be doing some blogging about it. The introductory chapter makes some bold claims about the efficiency of the language, both as in terms of run time efficiency and code density. The chapter also suggests that we will find the type system as flexible and intuitive as a dynamic language while still retaining the performance and correctness of a strongly typed language. Further, it states that often, if you manage to get your code compiled, it is correct. In short, the book promises the performance and typesafety of C++ and the flexibility of Ruby.