four.groovy

class Card
  String suit() { 'Spades' }
  int rank() { 4 }
  String color() { 'black' }
end

class Card
  String suit() { 'Hearts' }
  int rank() { 4 }
  String color() { 'red' }
end

class Card
  String suit() { 'Diamonds' }
  int rank() { 4 }
  String color() { 'red' }
end

class Card
  String suit() { 'Clubs' }
  int rank() { 4 }
  String color() { 'black' }
end