Julio Santos

This is a great book. It’s very short, less than 200 pages, with not that much text in them, and still it has a lot of interesting content.

The style is unconventional, which might be surprising at first, but it’s easy to get used to. Rather than tell you about Scheme, the author asks you questions, making you think and provide your own answers. “It this a list?” -> No, “Why not?” -> Because blah, “How to make it a list?” -> This way …, etc.

Each page is split into two columns, with the left hand column being a question to you, and the right hand column the proper answer. The questions start very slow, and each question is only incrementally more difficult than the previous one.

If you want to learn Scheme, this is certainly one of the books I would recommend, perhaps even the first book you should read (I think I said that about a couple of Scheme books, but this time I mean it…I think). When you do, don’t get too impatient and skip any questions. Try to stick to the easy and simple steps, one by one. Try and do the exercises which are very short, not a whole lot of code to write. Get a scheme interpreter to help you experiment. I like DrScheme.

At the end of the book, you will have covered a lot of material. More than I had anticipated it was possible in not even 200 pages, using this question-answer approach.

You’ll learn the 10 commandments of writing a Scheme program (10 easy to follow rules). You’ll know how to manipulate lists: create, add, remove, count, merge, etc. All this stuff will build your Scheme muscles and prepare you for the last 3 chapters.

In chapters 8, 9 and 10, the author covers the really interesting stuff: Lambda calculus, the Y-Combinator and the Meta-Circular Evaluator (or how to write a Scheme interpreter in Scheme). All in a matter-of-fact way.

When you’re done with the book, you’ll have some deep understanding of Scheme though you won’t know everything there is to know about Scheme yet. Closures for example.

Next on the list should be The Seasoned Schemer and The Reasoned Schemer.