The "Adventures of a Pythonista in Schemeland" is a long running series. The first six episodes were just the introduction. The real series begins now. I think it is fair to warn the reader about a change of attitude.
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
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!