Feature request: provide indication on sys.inputs that pandoc is running

[ntjess]

Given the minimal support for context and other potential quirks of pandoc interpretation, it might be nice for docs to know whether pandoc is processing them and simplify their layout accordingly.

One way typst supports environment conditions is through sys.inputs.

So ideally, we could write the following code:

#let template = something-complex-using-context
#if sys.inputs.at("pandoc-version", default: "").match("2\.[0-9]+") != none {
  template = doc => doc
}

and it would handle this case (or other version-specific pandoc constraints).

This is unlikely to introduce breaking changes, and providing a version number instead of true/false allows more backwards compatibility if new features are implemented.

Use case: I use pandoc to create readme's of typst libraries that render their example code into outputs (here's an example). However, this gets difficult when pandoc can't correctly interpret the rendered example code. Ideally, I could tell pandoc within the document to ignore these blocks when running.

Packages could also use this to insert phrases like "this document only compiles on pandoc 3.4.x+." or to panic with more informative error messages.

[jgm]

That's a nice idea. But since the typst interpreter is from the typst package, maybe it makes more sense to set sys.inputs.at("typst-hs version")? Indeed, the typst interpreter doesn't know the pandoc version.

[ntjess]

typst-hs-version makes sense to me. Would there be any benefit to also including the pandoc version?

[jgm]

I don't see how to include the pandoc version. The interpretation of typst code is done by typst-hs, and it doesn't know the pandoc version.