cards.ml

(* It's code I wrote while solving a problem in a Functional Programming course in December 2016 *)
(* Coming from OOP, I love how elegant and readable it is *)

fun card_value ( card : card ) =
  case card of
    ( _, Num i ) => i
  | ( _, Ace ) => 11
  | ( _, _ ) => 10
  
fun sum_cards ( cs : card list ) =
  let
    fun sum ( cs, acc ) =
      case cs of
        [] => acc
        | c :: cs' => sum ( cs', acc + card_value c )
  in
    sum ( cs, 0 )
  end
 
 val test = sum_cards [(Clubs, Num 2),(Clubs, Num 2)] = 4