-- Make a pack of cards.
mkPack :: [Face] -> [Suit] -> [Card]
mkPack faces suits =
    let vs = cartProduct faces suits
    in  map (\(v, s) -> Card v s) vs
mkPack :: [Face] -> [Suit] -> [Card]
mkPack faces suits =
    let vs = cartProduct faces suits
    in  map (\(v, s) -> Card v s) vs
mkPack faces suits =
    let vs = cartProduct faces suits
    in  map (\(v, s) -> Card v s) vs