OCaml wishlist posted September 2022

I've been writing (although mostly reading) OCaml on-and-off this last year. It's been quite a painful experience, even though I had some experience with functional languages already (erlang, which I really liked).

I find the language and the experience very close to C in many ways, while at the same time boasting a state of the art type system. It's weird. I think there's a real emphasis on the expressiveness, but little on the engineering. Perhaps this is due to the language not having enough traction in the industry.

So about this, I have two things I'd like to say. The first, is that if you're looking for a somewhat low-level (there's a garbage collector) language you can make a real dent in, OCaml might be the one. It's pretty bare bone, not that many libraries exist, and if they do they are barely usable due to a lack of documentation. My first contribution was a library to encode and decode hexadecimal strings, because I couldn't find one that I could use. That should tell you something.

My second contribution was a tool to build "by example" websites. I used it to make a website to learn OCaml by examples, and another one to learn Nix by example. How cool would it be if people started using it to build a number of "by examples" websites in the OCaml ecosystem :D?

Anyway, I digress, the second thing I wanted to say is: if you're working on OCaml (or want to contribute to a new language), here's my wishlist:

• a tool like cargo to manage dependencies (& versions), start projects, run tests, etc. Two important things: it should use a real configuration language (e.g. toml, json, yml) and it should work in a convention over configuration model.
• better integration with vscode. Every time I write or read OCaml I find myself missing rust-analyzer and its integration with vscode. I just want to be able to go to definitions, even in the presence of functors, and easily find the types of things (and see their implementations).
• being able to run a single test. It is crazy to me that today, you still can't write an inline test and run it. It's the best way to debug or test something.
• better compiler error messages. I think the lack of a tool like cargo, and this, are the biggest impediment to the language. See this issue for an example.
• better default for ocamlformat. OCaml is hard to read, some of the reasons are hard to change, but the formatting can be fixed and it really needs some work.
• a linter like clippy. It's 2022, every project should be able to run an OCaml linter in CI.
• good documentation for stdlib and 3rd party libraries. Documentation is really subpar in OCaml.
• a use keyword to import specific values in scope (as opposed to "opening" a whole module in scope)

PS: would someone actually be interested to work on any of these for a grant? There's a number of new-ish companies in the OCaml space that would probably pay for someone to solve these. I guess reach out to me on the contact page if you're interested.