Regression in syntax highlighting for Typst in 1.10

[christopherkenny]

I have:

• searched the issue tracker for similar issues
• installed the latest version of Quarto CLI
• formatted my issue following the Bug Reports guide

Bug description

Typst now uses skylighting by default, but this only implements a subset of features for text highlighting. As such, blocks now miss highlighting on common R features like pipes |>.

I believe the change to skylighting was intentional, but should likely be idiomatic by default to have both (1) better highlighting and (2) match pandoc defaults.

Steps to reproduce

Render the following using 1.9.36 or 1.10.0

---
title: example
authors:
  - Christopher T. Kenny
format:
  typst:
    keep-typ: true
---

{{< lipsum 1 >}}

```{r}
dplyr::starwars |> 
  dplyr::glimpse()
```

Actual behavior

It no longer styles the pipe:

Expected behavior

It should have a styled pipe. This is restored by changing to idiomatic, which is the default for pandoc:

---
title: example
authors:
  - Christopher T. Kenny
format:
  typst:
    keep-typ: true
    syntax-highlighting: idiomatic
---

{{< lipsum 1 >}}

```{r}
dplyr::starwars |> 
  dplyr::glimpse()
```

Your environment

• IDE: RStudio 2026.04.0 Build 439 (Daily build) / Positron 2026.03.0-212 (stable release)
• Windows 11

Quarto check output

Quarto 1.10.0
[>] Checking environment information...
      Quarto cache location: C:\Users\chris\AppData\Local\quarto
[>] Checking versions of quarto binary dependencies...
      Pandoc version 3.8.3: OK
      Dart Sass version 1.87.0: OK
      Deno version 2.4.5: OK
      Typst version 0.14.2: OK
[>] Checking versions of quarto dependencies......OK
[>] Checking Quarto installation......OK
      Version: 1.10.0
      Path: C:\Users\chris\AppData\Local\Programs\Quarto\bin
      CodePage: 1252

[>] Checking tools....................OK
      TinyTeX: (external install)
      Chromium: (not installed)
      Chrome Headless Shell: (not installed)
      VeraPDF: (not installed)

[>] Checking LaTeX....................OK
      Using: TinyTex
      Path: C:\Users\chris\AppData\Roaming\TinyTeX\bin\windows\
      Version: 2026

[>] Checking Chrome Headless....................OK
      Using: Chrome found on system
      Path: C:\Program Files\Google\Chrome\Application\chrome.exe
      Source: Windows Registry

[>] Checking basic markdown render....OK

[>] Checking R installation...........OK
      Version: 4.5.2
      Path: C:/PROGRA~1/R/R-45~1.2
      LibPaths:
        - C:/Users/chris/AppData/Local/R/win-library/4.5
        - C:/Program Files/R/R-4.5.2/library
      knitr: 1.51
      rmarkdown: 2.30

[>] Checking Knitr engine render......OK

[>] Checking Python 3 installation....(None)

      Unable to locate an installed version of Python 3.
      Install Python 3 from https://www.python.org/downloads/

[>] Checking Julia installation...

[mcanouil]

I believe the goal for 1.10 is to fix the syntax-highlighting and why it was set to idiomatic in 1.9. You can find the PR/issues about this.

[mcanouil]

@christopherkenny

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[christopherkenny]

Sorry, I did see the other issue and PR-workarounds, but I believe this is distinct. It is not set to idiomatic when I believe it should be by default to keep in line with pandoc behavior (and avoid the diminished highlighting).

[mcanouil]

That's not a regression.
The end goal is to provide the same styling for all formats.

See the changelog:

• quarto-cli/news/changelog-1.9.md

  Line 87 in d577ef4

  - ([#13878](https://github.com/quarto-dev/quarto-cli/issues/13878)): Typst now uses Pandoc's skylighting for syntax highlighting by default (consistent with other formats). Use `syntax-highlighting: idiomatic` to opt-in to Typst's native syntax highlighting instead.

[christopherkenny]

It is a regression, as moving from an old version to a new version introduces worse behavior on a feature which previously worked well.

Perhaps the more important point is that even Pandoc does not default to Skylighting. My understanding from the maintainers of this project from the discussion that introduces many of the changes to Typst via pandoc for 1.9:

Let me add a bit of context to some of our design goals and decisions, so that you understand where we might land on eventual PRs you might make. Then I'll make some specific comments.

• We prefer "features" that work uniformly across formats
• We prefer our templates to feel familiar to users coming from "non-Quarto workflows" of that format
• We prefer our templates to feel familiar to users coming from "pure Pandoc workflows" for that format
  These three goals mean that we want Quarto to work, in general, as close to a "strict Pandoc superset".

Link to @cscheid's comment on my discussion post on this topic

This explicitly diverges from 2/3 of those points to provide end users with a styling subset, where the prior versions provided full styling.

[cderv]

Hi,

Thanks for the feedback.

This is not the first report of change and possible problems with pandoc's support for typst highlighting.

So I am starting to consider this is not a good idea to have change default considering some of the losses. It was made to have same styling on all formats.

That being said, let's look at the report here before jumping to conclusions Regarding your pipe style feedback, either it is a generic problem for all formats or there is an oversight in typst integration to use correct r.xml highlight. To be clear, when using pandoc's highlighting, the code cells should be highlighted and styled the same in all formats. So pipe style in typst output and html output should be the same.

I can't check right now as I am travelling I'll verify this.

Anyhow, I'll look into it more closely.

[mcanouil]

The "pipe" is styled in both cases (with and without idiomatic).

The difference of colour is not a bug, it's a difference of theme.

Typst's default theme has different colours:

• https://github.com/typst/typst/blob/c817e592b735ef77af5eed079d411369cf433362/crates/typst-library/src/text/raw.rs#L930-L967

Quarto's default theme:

• quarto-cli/src/resources/pandoc/highlight-styles/arrow-light.theme

  Lines 192 to 199 in d577ef4

  	"SpecialChar": {
  	"text-color": "#5E5E5E",
  	"background-color": null,
  	"bold": false,
  	"italic": false,
  	"underline": false
  	},
  	"DecVal": {

Which ends up in Typst as: #let SpecialCharTok(s) = text(fill: rgb("#5e5e5e"),raw(s)).

So, indeed "idiomatic" #d73948 (native Typst) is different from "arrow" #5e5e5e (Skylighting).
This one colour change is not the only difference between Typst theme and Arrow theme.

Note that because Skylighting and Typst does not tokenise languages the same way, having a matching theme is not really doable.

[mcanouil]

Here is a "Typst"-ish theme for Skylighting.

typst.theme

{
    "text-color": null,
    "background-color": "#e6e6e6",
    "line-number-color": "#74747c",
    "line-number-background-color": null,
    "text-styles": {
        "Normal": {
            "text-color": null
        },
        "Other": {
            "text-color": "#d73948",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Attribute": {
            "text-color": "#4b69c6",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "SpecialString": {
            "text-color": "#198810",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Annotation": {
            "text-color": "#301414",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Function": {
            "text-color": "#4b69c6",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "String": {
            "text-color": "#198810",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "ControlFlow": {
            "text-color": "#d73948",
            "background-color": null,
            "bold": true,
            "italic": false,
            "underline": false
        },
        "Operator": {
            "text-color": "#1d6c76",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Error": {
            "text-color": "#d73948",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "BaseN": {
            "text-color": "#b60157",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Alert": {
            "text-color": "#d73948",
            "background-color": null,
            "bold": true,
            "italic": false,
            "underline": false
        },
        "Variable": {
            "text-color": "#8b41b1",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "BuiltIn": {
            "text-color": "#4b69c6",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Extension": {
            "text-color": "#4b69c6",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Preprocessor": {
            "text-color": "#16718d",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Information": {
            "text-color": "#74747c",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "VerbatimString": {
            "text-color": "#6b6b6f",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Warning": {
            "text-color": "#d73948",
            "background-color": null,
            "bold": false,
            "italic": true,
            "underline": false
        },
        "Documentation": {
            "text-color": "#74747c",
            "background-color": null,
            "bold": false,
            "italic": true,
            "underline": false
        },
        "Import": {
            "text-color": "#16718d",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Char": {
            "text-color": "#198810",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "DataType": {
            "text-color": "#d73948",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Float": {
            "text-color": "#b60157",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Comment": {
            "text-color": "#74747c",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "CommentVar": {
            "text-color": "#74747c",
            "background-color": null,
            "bold": false,
            "italic": true,
            "underline": false
        },
        "Constant": {
            "text-color": "#b60157",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "SpecialChar": {
            "text-color": "#d73948",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "DecVal": {
            "text-color": "#b60157",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        },
        "Keyword": {
            "text-color": "#d73948",
            "background-color": null,
            "bold": false,
            "italic": false,
            "underline": false
        }
    }
}

---
title: example
format:
  typst+quarto:
    syntax-highlighting: typst.theme
    output-file: "quarto.pdf"
  typst+native:
    syntax-highlighting: idiomatic
    output-file: "native.pdf"
---

```r
"Hello, world!" |> print()
x <- 1:10 + 1L
y <- x |> log()
```

[cderv]

Oh thanks! I assume it was deeper. So it is a style change because now all formats use the same default Quarto style arrow.

This was indeed expected, as previously Typst was the only format that did not default to the same style as the others. Previously, it was not possible to have typst use pandoc's style file, and now it is, so we switched.

And now there are two questions:

• a matter of arrow style choice. The highlighter does use r.xml, which does highlight the pipe |> - with class="sc" or SpecialChar internal node. Then arrow.theme applies, which sets this #5e5e5e color. The arrow style was created a while back to provide a good default for accessibility. There is an opportunity to revisit it - or maybe |> should not be assigned sc class 🤔

• a matter of overall default. Pandoc does not use the same default by using idiomatic value, but we did the change in Quarto to match the style in all outputs, and in the idea to bring missing features. So now all formats uses arrow style we created.
  Maybe this was no the right call after all, considering also what we needed to 'patch' already before 1.9 release.
  Also, possibly for this arrow theme being the default in all formats, we could change Typset's default to have this style in all docs that use Skylighting.

I'll discuss with the team. Thanks a lot for sharing your concerns.

[mcanouil]

FYI, Typst considers |> as any other operators. Other also does not exist at all in Typst.

[christopherkenny]

Thank you both for the response. My apologies on not understanding that it was a default theme difference, rather than the overall skylighting.

I understand the point about standardizing across formats, so I see where the change comes from. I would reiterate that this is a specific feature where pandoc opts not to use skylighting and Typst has very strong default behavior.

Appreciate your attention to this!