The book starts with a basic introduction to the type system and more importantly the implementation of it. It then moves on to functions again with a analogies to the object oriented world and with basic examples.
What I like about the book
Finally, it is a short book and to me that is a big plus.
What I miss in the book
My biggest complaint is that I would like more spelled out recommendations as to what and when the different language features and pattern.
The examples are very simplistic and similar, a few larger more realistic ones would have helped med tie it more to real problems.
Full Disclosure: [This book was reviewed as a part of the O'Reilly Blogger Review Program]