In the first cycle - the introductory episodes - my goal was to reach the great public: everybody could read the episodes without knowing Scheme at all. The topics I discussed, such as the difference between iteration and recursion and the dangers of the benchmarks, where language-independent and (hopefully) interesting for all readers.

However, now I will begin to discuss the peculiar features of Scheme. The second cycle will be a six-part introduction to Scheme macros, whereas the next one will discuss many functional techiques. Actually, Scheme allows a whole set of programming techniques with no equivalent in Python or in any other language: that means that you cannot rely on previous knowledge and that you have to make an effort in order to understand them.

If you want to follow the next Adventures, reading the articles will not be enough: you will need to write too. I expect my reader to download a Scheme implementation and to start writing down toy programs. The series will give some hints and code challenges, but it will be up to you to implement them.

I expect to lose a few readers, since many people will not have the time to follow the series closely, but so be it. I do not want to follow the approach of dumbing down the language and therefore losing the point of it. I will make an effort to make things as simple as possible, but not simplest.

Scheme is not a language for everybody, yet the series is not meant to be elitist, and actually it should be much easier to follow than a textbook or the R6RS document itself.

I have a note for my Italian readers, the ones who read the original version of this series. Whereas the articles in the first cycle are a close translation of the originals, the articles in the second cycle (starting from episode #9) are quite different.

The reason is that I have decided to change my presentation about macros and not to talk about syntax-rules macros directly, for pedagogical purposes. Therefore, you may want to read the English version even if you have already read the Italian version.

Conversely, people reading the English version may want to give a look at the Italian version too (you can use Google Translator or just look at the code) since it describes more advanced techniques that in the English version will be discussed in a future cycle.

If you have comments of any kind (did you like the series so far?) you are invited to post them here.

I will see you in episode #7, if you are interested in list processing!

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