Add Nickel language

[ErinvanderVeen]

Resolves #1809

[the-mikedavis]

It looks like fun is missing a highlight. If you move this up to the top of the file and add fun it'll highlight as a keyword:

["fun" "forall" "default" "doc"] @keyword

[ErinvanderVeen]

I think your review was a little early. "fun" should be highlighted, I query for fun_expr and within that for "fun".

[the-mikedavis]

Ah yep I was on an old revision. I see the fun highlight now 👍

[the-mikedavis]

What do you think about for a highlight of the => arrow in a function? I think in languages with similar features we've used @operator before

"=>" @operator

[ErinvanderVeen]

That does sound like a good idea. I'll add that.

[ErinvanderVeen]

This PR tweag/nickel#681 should land soon, adding a new rec keyword to the language, which will also involve an update to the tree-sitter grammar. It's up to you if you think it best to wait for that. I expect it will be merged before the end of this week.

[the-mikedavis]

looks good, thanks!

[the-mikedavis]

I think we'll just merge this now and the rec update can be a follow up 👍