TextArea syntax highlighting for multi-language code

[TomJGooding]

Currently the TextArea syntax highlighting works based on a single defined language, but often code can contain multiple different languages. The obvious example is HTML which can contain JavaScript inside of <script> tags and CSS inside of <style> tags. But also TypeScript syntax highlighting should include the JavaScript as well as the added types.

[darrenburns]

I think this is probably beyond the scope of what we'd want to offer out of the box, but we should definitely think about how it could be achieved by someone who wishes to add that functionality.

tree-sitter offers a mechanism for this: https://tree-sitter.github.io/tree-sitter/using-parsers#multi-language-documents

However, it appears that the set_included_ranges function is not available as part of the Python bindings.

[TomJGooding]

Thanks Darren, I do appreciate this might be out of scope especially if it would require a lot of work!

I haven't looked into this in much depth yet, but there's also the feature of language injection which might be useful? I'm not sure if this would still require set_included_ranges though...