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<article> <h2>OCaml mode</h2>

<textarea id=“ocamlCode”> (* Summing a list of integers *) let rec sum xs =

match xs with
  | []       -&gt; 0
  | x :: xs' -&gt; x + sum xs'

(* Quicksort *) let rec qsort = function

| [] -&gt; []
| pivot :: rest -&gt;
    let is_less x = x &lt; pivot in
    let left, right = List.partition is_less rest in
    qsort left @ [pivot] @ qsort right

(* Fibonacci Sequence *) let rec fib_aux n a b =

match n with
| 0 -&gt; a
| _ -&gt; fib_aux (n - 1) (a + b) a

let fib n = fib_aux n 0 1

(* Birthday paradox *) let year_size = 365.

let rec birthday_paradox prob people =

let prob' = (year_size -. float people) /. year_size *. prob  in
if prob' &lt; 0.5 then
    Printf.printf "answer = %d\n" (people+1)
else
    birthday_paradox prob' (people+1) ;;

birthday_paradox 1.0 1

(* Church numerals *) let zero f x = x let succ n f x = f (n f x) let one = succ zero let two = succ (succ zero) let add n1 n2 f x = n1 f (n2 f x) let to_string n = n (fun k -&gt; “S” ^ k) “0” let _ = to_string (add (succ two) two)

(* Elementary functions *) let square x = x * x;; let rec fact x =

if x &lt;= 1 then 1 else x * fact (x - 1);;

(* Automatic memory management *)

let l = 1
2
3

[];;

[1; 2; 3];;

5

l;;

(* Polymorphism: sorting lists *) let rec sort = function

| [] -&gt; []
| x :: l -&gt; insert x (sort l)

and insert elem = function

| [] -&gt; [elem]
| x :: l -&gt;
    if elem &lt; x then elem :: x :: l else x :: insert elem l;;

(* Imperative features *) let add_polynom p1 p2 =

let n1 = Array.length p1
and n2 = Array.length p2 in
let result = Array.create (max n1 n2) 0 in
for i = 0 to n1 - 1 do result.(i) &lt;- p1.(i) done;
for i = 0 to n2 - 1 do result.(i) &lt;- result.(i) + p2.(i) done;
result;;

add_polynom [| 1; 2 |] [| 1; 2; 3 |];;

(* We may redefine fact using a reference cell and a for loop *) let fact n =

let result = ref 1 in
for i = 2 to n do
  result := i * !result
 done;
 !result;;

fact 5;;

(* Triangle (graphics) *) let () =

ignore( Glut.init Sys.argv );
Glut.initDisplayMode ~double_buffer:true ();
ignore (Glut.createWindow ~title:"OpenGL Demo");
let angle t = 10. *. t *. t in
let render () =
  GlClear.clear [ `color ];
  GlMat.load_identity ();
  GlMat.rotate ~angle: (angle (Sys.time ())) ~z:1. ();
  GlDraw.begins `triangles;
  List.iter GlDraw.vertex2 [-1., -1.; 0., 1.; 1., -1.];
  GlDraw.ends ();
  Glut.swapBuffers () in
GlMat.mode `modelview;
Glut.displayFunc ~cb:render;
Glut.idleFunc ~cb:(Some Glut.postRedisplay);
Glut.mainLoop ()

(* A Hundred Lines of Caml - caml.inria.fr/about/taste.en.html *) (* OCaml page on Wikipedia - en.wikipedia.org/wiki/OCaml *) </textarea>

<h2>F# mode</h2> <textarea id=“fsharpCode”> module CodeMirror.FSharp

let rec fib = function

| 0 -> 0
| 1 -> 1
| n -> fib (n - 1) + fib (n - 2)

type Point =

{
    x : int
    y : int
}

type Color =

| Red
| Green
| Blue
0 .. 10

|> List.map ((+) 2) |> List.fold (fun x y -> x + y) 0 |> printf “%i” </textarea>

<script>

var ocamlEditor = CodeMirror.fromTextArea(document.getElementById('ocamlCode'), {
  mode: 'text/x-ocaml',
  lineNumbers: true,
  matchBrackets: true
});

var fsharpEditor = CodeMirror.fromTextArea(document.getElementById('fsharpCode'), {
  mode: 'text/x-fsharp',
  lineNumbers: true,
  matchBrackets: true
});

</script>

<p><strong>MIME types defined:</strong> text/x-ocaml (OCaml) and text/x-fsharp (F#).</p> </article>