Possible syntax highlighting collaboration

[mattmassicotte]

I literally just finished watching the presentation of DeckUI at Deep Dish, and one part really spoke to me. I've worked a bunch with syntax highlighting, and in fact maintain a number of Swift packages that could potentially be useful. Now the stuff I do may not be a perfect fit, because it is all built to back a general-purpose text editing system. However, it can definitely still do static text.

Neon (https://github.com/chimeHQ/Neon) is a highlighting system.
SwiftTreeSitter (https://github.com/chimeHQ/SwiftTreeSitter) is the component that pulls out the syntactic info needed for highlighting.

I think the largest issue is probably with how the tree-sitter works, specifically how you support a language grammar. Each language requires its own Swift package. I've been (very slowly) SPM-ifying the language grammars themselves, but it isn't that hard and there's almost certainly tree-sitter support for whatever language might be of interest.

I figured I'd open up an issue first to talk about it, because in some ways this could be a great collaboration. Also, I’m not sure how this could be more of an over-engineered solution, so seemed appropriate.

[mattmassicotte]

Ok, so I've thought on this some more. I'm now no longer sure Neon is even needed in the static highlighting case. So really, what this could look like is:

• Add SwiftTreeSitter as a dependency
• Read out the language annotation from the markdown code block
• Hunt for a grammar bundle matching that that (SwiftTreeSitter can kinda do this now)
• Load the language or spit out a warning saying you need to add the per-language SPM package (yes this kinda sucks)
• Run the highlights query to get semantic info about the tokens/ranges
• Apply a theme*

All this really isn't too much work, except for the stupid theme part. Tree-sitter pulls out semantic information, but doesn't actually apply colors. This is actually a problem I've wanted to address for a while, so I put together a new repo that I think can bridge the gap between token labels and string attributes. However, it is totally non-functional at the moment.

https://github.com/ChimeHQ/ThemePark

[mattmassicotte]

Just following up here, its been a while now! That ThemePark library is now completely functional and supports Xcode, TextMate, and BBEdit theme formats to various degrees.

So, this is now completely implemenatable!