RiK0 Tech Temple: Excellent Learn You a Haskell for Greater Good

This is the third book explicitly about Haskell I directly buy (a part from things such as Functional Data Structers or Pearls of Functional Algorithm Design), the others being Haskell School of Expression and Real World Haskell, plus some online tutorials and freely available books. I believe they are all excellent books, although with slightly different focus. They come from different ages as well (with HSOE being quite holder).

Back then I enjoyed a lot HSOE, but I think I missed something. Large part of the book used libraries not easily available on the Mac, for example. Moreover, the book did not use large parts of the Haskell standard library which are very useful. For that and other reasons, I did not go on working with Haskell. Real World Haskell has a very practical focus and I quite enjyoed that. Unfortunately, I still remembered too much Haskell not to "jump" the initial parts of the book (and that is usually a bad thing, because you don't get comfortable with the author style before jumping to more elaborate subjects). Moreover, the book is quite massive and I had other stuff to do back then (like graduating).

I did not even want to buy LYHFGG. Afterall, I am a bit skeptical over using Haskell for real world stuff (I prefer more pragmatic languages like Python or Clojure) and so I tried to resist the urge to buy another Haskell book (I could finish RWH, afterall). For a combination of events I did not even remember, I put the book in an amazon order. Understanding a couple of Haskell idioms could improve my clojure, I thought, and I started reading the book in no time.

The first part of the book is very well done but somewhat uninteresting. By the time I started reading it, I had forgotten most Haskell I knew and consequently I read that carefully: however, I made the mistake not to start a small project just to toy with the language. That is the reason I say "somewhat uninteresting": it is very basic, very easy and very clear. Still, I did only remind me of things I knew, without really improving my way of thinking much. Still, the writing was fun and light and I read through it quickly. I consider it a very good introduction to functional programming in Haskell and to functional programming in general and as such the tag line "a beginner guide" is well deserved.

Later in chapter 11 comes the real meat. Functors, Applicative Functors, Monoids and then Monads are presented. The order is excellent: after having learned Applicative Functors, Monads require only a small further understanding steps. Moreover, repeating all the reasoning on Maybe and lists really clarifies the thing. The examples were also in HSOE, but connecting the dots was somewhat left to the reader. This time I did not make the mistake to see monads as just a tool to implement state monad and reached a deeper insight on the subject.

About the book itself, I just love no starch press...