== operator for enum's in Solidity

Card.sol

contract Card
{
    enum Suit {Heart, Diamond, Shape, Club, Jocker}
    Suit public suit;
    
    enum Rank {Two, Three, Four, Five, Six, Seven, Eight, Nine, Ten, Jack, Queen, King, Ace, Jocker}
    Rank public rank;
    
    function equal(Card card) returns (bool)
    {
        return suit == card.suit && rank == card.rank;
    }
}

The above is failing with the following error

Card.sol:11:16: Error: Operator == not compatible with types enum Suit and function () returns (enum Suit)
        return suit == card.suit && rank == card.rank;
               ^---------------^
Card.sol:11:37: Error: Operator == not compatible with types enum Rank and function () returns (enum Rank)
        return suit == card.suit && rank == card.rank;

parenthesis are needed when referencing an enum variable as it is a function. The following code compiles

contract Card
{
    enum Suit {Heart, Diamond, Shape, Club, Jocker}
    Suit public suit;

    enum Rank {Two, Three, Four, Five, Six, Seven, Eight, Nine, Ten, Jack, Queen, King, Ace, Jocker}
    Rank public rank;

    function equal(Card card) returns (bool)
    {
        return suit == card.suit() && rank == card.rank();
    }
}