In many ways, this goes against the design philosophy of typst. Incremental compilation, that enables the expedient compilation we experience in the app, is due to the fact that there ain't any macros.

I think functions pretty much fill this role.

In many ways, this goes against the design philosophy of typst. Incremental compilation, that enables the expedient compilation we experience in the app, is due to the fact that there ain't any macros.

I see, thank you for responding. I really hope we get graphs and diagrams some day :^)

See https://gitlab.com/giacomogallina/typst-cd for a commutative diagrams example.

I think functions pretty much fill this role.

Functions suffer from scope limitations, while macro expansions occur in the caller's scope.

I'm somewhat frustrated by not being able to nicely encapsulate set page(...), or set heading(...) inside a function, thus separating code from formatting, as it simply won't work; however, "polluting" an user's source file with show and set rules is the only way (at least I know of, and I've been typst'ing a lot lately) to make those instructions to being into effect.

The following does not work:

#let apply-intended-formattings() = {
  // my code-oriented including `set` and `show` rules,
  // which can be placed in another, package-side source file, but shown here for conciseness...
}

// user source:
#apply-intended-formattings()
// Bummer! the changes likely fell out-of-scope and do not seem to work at all...

But the following, that mixes code with document contents, does:

//user source interspersed with lots of `set` and `show` rule codes.
= Headings
And text concerning the writer, all mixed up.

Another (related) form to make this work is by having the ability to global set, and global show within functions, as discussed on #2153.

@cnaak What you want to do in this case is use a bare show rule to pass the rest of your document into the function. Rather than pulling out the styling and making it global somehow, you push in the content, making it local. It would look like this:

#let apply-intended-formattings(body) = {
  set document(title: "My Title")
  set page(paper: "a5")
  set text(size: 12pt)
  body
}

#show: apply-intended-formattings
This is affected!

Effectively show: f; The rest is equivalent to #f[The rest].

See also https://typst.app/docs/tutorial/making-a-template/