CodeMirror: OCaml mode

(* Summing a list of integers *)
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(* Summing a list of integers *)
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let rec sum xs =
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  match xs with
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    | []       -> 0
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    | x :: xs' -> x + sum xs'
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(* Quicksort *)
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let rec qsort = function
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   | [] -> []
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   | pivot :: rest ->
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       let is_less x = x < pivot in
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       let left, right = List.partition is_less rest in
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       qsort left @ [pivot] @ qsort right
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(* Fibonacci Sequence *)
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let rec fib_aux n a b =
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  match n with
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  | 0 -> a
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  | _ -> fib_aux (n - 1) (a + b) a
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let fib n = fib_aux n 0 1
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(* Birthday paradox *)
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let year_size = 365.
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let rec birthday_paradox prob people =
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    let prob' = (year_size -. float people) /. year_size *. prob  in
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    if prob' < 0.5 then
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        Printf.printf "answer = %d\n" (people+1)
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    else
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        birthday_paradox prob' (people+1) ;;
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birthday_paradox 1.0 1
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(* Church numerals *)
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let zero f x = x
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let succ n f x = f (n f x)
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let one = succ zero
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let two = succ (succ zero)
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let add n1 n2 f x = n1 f (n2 f x)
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let to_string n = n (fun k -> "S" ^ k) "0"
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let _ = to_string (add (succ two) two)
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(* Elementary functions *)
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let square x = x * x;;
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let rec fact x =
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  if x <= 1 then 1 else x * fact (x - 1);;
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(* Automatic memory management *)
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let l = 1 :: 2 :: 3 :: [];;
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[1; 2; 3];;
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5 :: l;;
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(* Polymorphism: sorting lists *)
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let rec sort = function
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  | [] -> []
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  | x :: l -> insert x (sort l)
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and insert elem = function
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  | [] -> [elem]
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  | x :: l -> 
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      if elem < x then elem :: x :: l else x :: insert elem l;;
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(* Imperative features *)
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let add_polynom p1 p2 =
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  let n1 = Array.length p1
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  and n2 = Array.length p2 in
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  let result = Array.create (max n1 n2) 0 in
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  for i = 0 to n1 - 1 do result.(i) <- p1.(i) done;
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  for i = 0 to n2 - 1 do result.(i) <- result.(i) + p2.(i) done;
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  result;;
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add_polynom [| 1; 2 |] [| 1; 2; 3 |];;
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(* We may redefine fact using a reference cell and a for loop *)
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let fact n =
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  let result = ref 1 in
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  for i = 2 to n do
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    result := i * !result
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   done;
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   !result;;
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fact 5;;
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(* Triangle (graphics) *)
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let () =
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  ignore( Glut.init Sys.argv );
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  Glut.initDisplayMode ~double_buffer:true ();
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  ignore (Glut.createWindow ~title:"OpenGL Demo");
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  let angle t = 10. *. t *. t in
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  let render () =
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    GlClear.clear [ `color ];
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    GlMat.load_identity ();
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    GlMat.rotate ~angle: (angle (Sys.time ())) ~z:1. ();
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    GlDraw.begins `triangles;
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    List.iter GlDraw.vertex2 [-1., -1.; 0., 1.; 1., -1.];
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    GlDraw.ends ();
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    Glut.swapBuffers () in
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  GlMat.mode `modelview;
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  Glut.displayFunc ~cb:render;
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  Glut.idleFunc ~cb:(Some Glut.postRedisplay);
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  Glut.mainLoop ()
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(* A Hundred Lines of Caml - http://caml.inria.fr/about/taste.en.html *)
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(* OCaml page on Wikipedia - http://en.wikipedia.org/wiki/OCaml *)
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