Add markdown rendering to MLX Chat Example

[davidkoski]

Add markdown rendering to MLX Chat Example:

The MLXLLMEval has an integration with swift-markdown-ui -- perhaps we could use that here.

[Kawba]

Created a PR for this as I've been doing something similar in my app.

It's just a super simple, no external deps, way of supporting markdown with the Text view you are already using, as it is supported out of the box with the right data type.

As I mentioned in the PR, others may want to look into more custom ways of doing this if they want stuff like supporting GitHub flavour of markdown or selectable text on iOS/iPadOS. I added a suggestion for the text selection one because even swift-markdown-ui does a bad job of it (see the issue on their repo).

If you're happy to do it this way, I'm happy to make any changes required, as it was just a quick PoC :)

Thanks,
Kawba

[davidkoski]

I think I have seen models output tables in markdown -- does this support that? Need to find a prompt that does it (assuming I am remembering correctly).

[Kawba]

Tables are one of the things that are not part of the original markdown spec (part of GitHub flavour in the format most people use).

If that's a requirement to support, "swift-markdown-ui" as you said may be the best option. Although I think people should be aware of the text selection issue (Cannot select across paragraphs and on iOS/iPadOS you can not do accurate selection, just entire paragraphs in one go - gonzalezreal/swift-markdown-ui#264).

Would you like me to modify my PR to use "swift-markdown-ui"?

[davidkoski]

Yeah, the broken selection is not great. Perhaps simplicity and correct behavior should outweigh features :-)

I will take a look at the PR tomorrow!

[JoeJoe1313]

I think the approach in LLMEval to use MarkdownUI and introduce a toggle allowing for text/markdown selection is a good solution. I attempted to implement it in the following PR, so far it's working even during text generation. I will update the testing done section with some screenshots. This would be a somewhat good workaround for the broken selection in MarkdownUI.

[Kawba]

I still kind of feel as though a sample app should keep it simple and just use the Text view, that said if we do go down the route of a toggle I'd argue it should be swift-markdown-ui on one side and the other should be SelectableText (with MarkdownToAttributedText for markdown parsing) as it renders the same level of markdown as the normal text view but with greatly improved selection experience across all platforms.

I