Playground Ocaml

Simple, Fast interactive Playground for functional stuffs.

Syntax

- Variable is immutable by default : need ref / := / !var for mut mode.
- comma ; in the end of every statement.
- comment as (* COMMENT *).
  
- let .. in : for every declare.
- let rec .. in : recursive fn.

- while .. do .. done : as loop.
- if .. then .. else = fixed default.
  
- % is mod in Ocaml.
- ^ is string concat.

- Ctypes.CArray : for c interop / FFI stuffs -> get/set/length()

- Ocaml use Dune to build / exec / run project.
- Ocaml use Opam as package manager.

Installation on Ubuntu 25.04

I assume a stable version by now is ocaml 5.4.0 + dev-repo of ocamlformat ocaml-lsp-server

1. Install via APT instead of curl :

    sudo apt install opam
   

2. Fix Ocaml Language Server in Editors :

    opam pin add ocaml-lsp-server https://github.com/ocaml/ocaml-lsp.git
   

3. Update ocamlformat to fit 5.4.0 :

    opam pin --dev-repo ocamlformat
   

Experience

Ocaml have some quite tricky stuffs when I transfer from imperative language. Even when I have used F# like 10 years ago with more forgiveness, still cost me a night to figure out differences. Perhaps Rust eased a lot of things for me like mut stuffs. Although a lot of example/pratices were shorter than Odin, they tend to take me more time to fix stuffs I already have forgotten about ML, again, Rust spoiled me way too much for its convenient syntax rules (except borrow-checker & eyes-hurt stuffs).