[CD] OCAML basics

core/cd/summary/code/ocaml/00_basics.ml

@@ -1 +1,36 @@
+(* comments are like this and can be nested *)
 let a_function (a : int) (b : int) : int = a * b
+
+(* We can use the following to print ANYTHING upon execution *)
+let () = Printf.printf "Format String (just like C's printf)"
+
+(* We can also use ; to sepearate statements. The last statement's value is returned
+ Furthermore, this definition of `a_function` shadows the previous one *)
+let a_function (a : int) : int =
+  Printf.printf "Print anything here";
+  a * a
+
+let vars_in_func (a : int) =
+  let x = a_function a in
+  Printf.printf "Value is %d" x
+
+(* This is a simple example of a generic funciton and pattern matching *)
+let is_empty (a : 'a list) : bool =
+  match a with
+  | [] -> true
+  | _ :: _ -> false (* The underscores are, just like in Haskell, wildcards *)
+
+let if_func (v1 : string) (v2 : string) : string =
+  if v1 = v2 then "match" else "no match"
+
+(* Recursive function *)
+let rec double_all (arg : int list) : int list =
+  match arg with [] -> [] | a :: al -> (a * a) :: double_all al
+
+(* Recursive Tail function. This is more efficient than the above because it's compiled
+to a simple loop. Furthermore, the fold functions behave in this way *)
+let double_all_t (arg : int list) : int list =
+  let rec aux a acc = match a with [] -> acc | v :: vl -> aux vl (v :: acc) in
+  List.rev (aux arg [])
+
+let print_list (list : 'a list) = List.iter (Printf.printf "%d") list