Following [Best Practices](https://nix.dev/guides/best-practices#with-scopes),
`with` is a problematic language construction and should be avoided.
Usually it is employed like a "factorization": `[ X.A X.B X.C X.D ]` is written
`with X; [ A B C D ]`.
However, as shown in the link above, the syntatical rules of `with` are not so
intuitive, and this "distributive rule" is very selective, in the sense that
`with X; [ A B C D ]` is not equivalent to `[ X.A X.B X.C X.D ]`.
However, this factorization is still useful to "squeeze" some code, especially
in lists like `meta.maintainers`.
On the other hand, it becomes less justifiable in bigger scopes. This is
especially true in cases like `with lib;` in the top of expression and in sets
like `meta = with lib; { . . . }`.
That being said, this patch removes most of example code in the current
documentation.
The exceptions are, for now
- doc/functions/generators.section.md
- doc/languages-frameworks/coq.section.md
because, well, they are way more complicated, and I couldn't parse them
mentally - yet another reason why `with` should be avoided!
e671d3bbbd