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Comment by maxbond | Hacker News Reader

I think it would be sufficient & more valuable to implement a language server for your new language, which keeps you focused on the parts related to your language rather than the struggles of implementing an editor, and then you'll be able to drop into VSCode, neovim, etc.

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Does anyone have an good intro tutorial for writing a language server in, say, C for some simple language? I find most of the docs a little too inscrutable to follow for just a bit of dabbling.

I agree with the parent. The big advantage of what he's suggesting is code objects exist as first class objects. They don't have to creased by parsing a text file. Which means the editor can directly manipulate them.

If you've ever used CAD programs especially Schematic Capture and PCB Layout programs you'll get the idea. Everything displayed on the screen is an object in a database.

Instead of a parser blindly parsing a text file and coming across a struct definition, a struct is object created by the programmer. Which means you can have hard links between the objects that make up the program. And those can be directly manipulated with manually or programmatically.

The big advantage comes from maintenance and refactoring. Change the name of a field? Happens in exactly one place in the program. So instead of a diff with 1537 files changes you have 'renamed struct fobar to struct foobar'. Change a comment? Well it's just a changed comment.

I'd like to see languages like that, but it's a massive lift. Our systems of source control and CI/CD are built around the assumption that languages are text files that are somewhat line oriented. It's valuable for people to be able to use different editors and tools, and text files are the integration point that makes this work.

Fallible parsers are a bit of a hack but they're a hack that works and is widely deployed already, and I'm not convinced the value of moving to a symbolic/binary representation creates enough value to justify the risk involved in the migration. That being said I'd love to see it happen. We'd end the tabs and spaces debate once and for all!

If you write your own editor with language server features, writing a language server implementation _should_ (dangerous word) be relatively easy. By writing the editor in your language, you prove that your language is actually useful for a real world problem. You also have the flexibility to add any functionality that you wish without contorting your thinking to whatever may be imposed on you by the lsp model.

It isn't necessarily clear to me that writing a language server implementation is that much easier than writing an editor. To be fair, I have personally done neither (though I have written REPLs) so perhaps I am wildly off in my estimation.

I don't really disagree, but would point out that, for the languages I hack on, they're DSLs that wouldn't be appropriate to write an editor in. I agree that you should be writing code in your language & solving problems with it though, even before there's a working implementation. It does really help hone your vision and focus on the problems you're solving.

I've not written a language server either, and I'm positive it's one or two orders of magnitude more difficult than a simple editor, but I think the time is better spent for many projects because it gets you into the nitty gritty mechanics of your language & sets you up for a good developer experience. If your language specializes in writing things like editors though, that would certainly not be the case.

Tangentially, my language development hot take is that YAML is a really great platform to start with, so you can focus on prototyping your runtime & semantics and kick the can on parsing & syntax. Parsing takes up a lot of time and you might not know if this language idea is worthwhile or not yet. Additionally, YAML is pretty darn good and you may never need to move off of it.

> for the languages I hack on, they're DSLs that wouldn't be appropriate to write an editor in

Ha, I have been working on a DSL for writing DSLs, which perhaps explains my perspective a bit.

Sounds cool! If you have something public I'd love to see it. Email is in my profile.

It's not quite ready to share but hopefully soon :)

Best of luck & happy hacking

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