`println!` adds references (&) to its arguments, to avoid moving them.
This is undesirable here, because it is extremely error-prone to take
references to `static mut`s. We could `println!("{}", {counter})`, but
this is somewhat exotic syntax and just sticking with `dbg!` also avoids
this problem as it does not add references.
The files in this directory make up the content of the course. The files here
can include third-party content from ../third_party/ as well.
When we publish a translation of the course, we git restore the src/ and
third_party/ directories at the repository root back to the date listed in the
POT-Creation-Date header of the translation. It is crucial, that all
translatable content lives in those two directories. The other files (such as
book.toml and theme/) are not restored and we always use the latest version
of them.
03df73e747