ocaml

2026-03-14 07:05:56 +01:00
parent c8bb7585ee
commit 9c57ea69f2
8 changed files with 149 additions and 0 deletions
--- a/ocaml/README.md
+++ b/ocaml/README.md
@@ -0,0 +1,3 @@
+_Climbing on the camel's back._ 🐫
+
+Experiments with OCaml, inspired by [Bobkonf](https://bobkonf.de) 2026.
--- a/ocaml/dune
+++ b/ocaml/dune
@@ -0,0 +1,5 @@
+(executable
+ (name main)
+ (modes js)
+ (libraries js_of_ocaml)
+ (preprocess (pps js_of_ocaml-ppx)))
--- a/ocaml/dune-project
+++ b/ocaml/dune-project
@@ -0,0 +1,2 @@
+(lang dune 3.10)
+(name ocaml_js_demo)
--- a/ocaml/flake.lock
+++ b/ocaml/flake.lock
@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1773282481,
+        "narHash": "sha256-b/GV2ysM8mKHhinse2wz+uP37epUrSE+sAKXy/xvBY4=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "fe416aaedd397cacb33a610b33d60ff2b431b127",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
--- a/ocaml/flake.nix
+++ b/ocaml/flake.nix
@@ -0,0 +1,73 @@
+{
+  description = "OCaml -> JavaScript demo using js_of_ocaml";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+  };
+
+  outputs =
+    { self, nixpkgs }:
+    let
+      system = "x86_64-linux";
+      pkgs = import nixpkgs { inherit system; };
+    in
+    {
+      devShells.${system}.default = pkgs.mkShell {
+        packages = with pkgs; [
+          ocaml
+          dune_3
+          ocamlPackages.js_of_ocaml
+          ocamlPackages.js_of_ocaml-compiler
+          nodejs
+          tmux
+          ocamlPackages.ocaml-lsp
+          ocamlPackages.ocamlformat
+          (pkgs.writeShellApplication {
+            name = "dev";
+            runtimeInputs = [ dune nodejs tmux ];
+            text = ''
+              SESSION=ocaml-js
+
+              tmux new-session -d -s "$SESSION"
+
+              tmux new-window -t "$SESSION" -n build
+              tmux send-keys -t "$SESSION:0" "dune build main.bc.js --watch" C-m
+
+              tmux new-window -t "$SESSION" -n server
+              tmux send-keys -t "$SESSION:1" "npx live-server result" C-m
+
+              tmux attach -t "$SESSION"
+            '';
+          })
+        ];
+        shellHook = ''
+          echo "Run 'dev' to start tmux dev environment."
+        '';
+      };
+
+      packages.${system}.default = pkgs.stdenv.mkDerivation {
+        pname = "ocaml-js-demo";
+        version = "0.1";
+
+        src = ./.;
+
+        nativeBuildInputs = with pkgs; [
+          ocaml
+          dune_3
+          ocamlPackages.js_of_ocaml
+          ocamlPackages.js_of_ocaml-compiler
+          ocamlPackages.js_of_ocaml-ppx
+        ];
+
+        buildPhase = ''
+          dune build main.bc.js
+        '';
+
+        installPhase = ''
+          mkdir -p $out
+          cp _build/default/main.bc.js $out/
+          cp index.html $out/
+        '';
+      };
+    };
+}
--- a/ocaml/index.html
+++ b/ocaml/index.html
@@ -0,0 +1,15 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>OCaml DOM demo</title>
+</head>
+<body>
+
+<h1 id="title">OCaml DOM Demo</h1>
+<button id="btn">Click me</button>
+<p id="output"></p>
+
+<script src="main.bc.js"></script>
+</body>
+</html>
--- a/ocaml/main.ml
+++ b/ocaml/main.ml
@@ -0,0 +1,23 @@
+open Js_of_ocaml
+(* open Js_of_ocaml.Dom_html *)
+
+let document = Dom_html.document
+
+let by_id id =
+  Js.Opt.get
+    (document##getElementById (Js.string id))
+    (fun () -> failwith ("Missing element: " ^ id))
+
+let () =
+  let button = by_id "btn" in
+  let output = by_id "output" in
+
+  let clicks = ref 0 in
+
+  button##.onclick :=
+    Dom_html.handler (fun _ ->
+      incr clicks;
+      output##.textContent :=
+        Js.some (Js.string ("Clicked " ^ string_of_int !clicks ^ " times"));
+      Js._false
+    )