Suggestions for syntax highlighting improvements

[jwortmann]

Here are a few suggestions and problems that I noticed:

It seems like the scope names for labels and references were chosen based on highlighting colors in the Mariana color scheme. They look good, but they are not really the correct scopes, and it might look worse in different color schemes - e.g. many other color schemes don't highlight the punctuation.definition scope.

References in the LaTeX syntax use constant.other.reference, so my suggestions for proper scopes would be

  <label>
//^ punctuation.definition.label.begin.typst
// ^^^^^ entity.name.label.typst
//      ^ punctuation.definition.label.end.typst

  @label
//^^^^^^ constant.other.reference.typst
//^ punctuation.definition.reference.typst
// ^^^^^ - punctuation

Unfortunately Mariana doesn't highlight entity.name.label, so maybe it would be acceptable in this case to keep the storage.modifier scope.

---

In math blocks, not every letter should get support.function.math.
Ideally this scope should only be used for known functions, and single letters should probably get variable.other.math - if it should follow the LaTeX syntax. And I would probably use support.constant for the known symbols, e.g. phi (this is indeed keyword in LaTeX, but I think it is wrong):

$ F_n = round(1 / sqrt(5) phi.alt^n) $
//^ variable.other.math
//  ^ variable.other.math
//      ^^^^^ support.function.math
//                        ^^^^^^^ support.constant

But I don't know if this is feasible, because there are a lot of built-in symbols and functions, and it would be annoying to manually type them all into the syntax. Maybe it could use variable.other.math for single letters and support.function.math for 2 or more letters, as a simple heuristic.

---

I would probably use variable.other for single variables in markup, instead of constant.other.symbol, and keyword for let, set, etc., like this:

  #let name = "Typst"
//^^^^^^^^^^^^^^^^^^^ meta.expression.typst
//^ punctuation.definition.expression.typst
// ^^^ keyword.declaration.typst
This is #name's documentation.
//      ^^^^^ variable.other.typst
//      ^ punctuation.definition.variable.typst

But the variable.other would probably make highlighting worse in most color schemes, because often it is not highlighted...

[hyrious]

First of all, thank you for your patience on keeping improving this plugin!

I basically implemented your suggestions in the past few commits. Some differences:

• Labels still get a storage.modifier to make it colored in other color schemes
• Added string.other scope to $ like LaTeX to make it colored in other color schemes
• Added keyword.other scope to # to make it colored in other color schemes
• Not using variable.other as they are almost not colored, keeping constant.other.symbol.

[jwortmann]

Excellent, closing as resolved.

If I find any other possible improvements, I can provide a PR, but the highlighting looks very good already.