Data update

Task/Abstract-type/Pluto/abstract-type.pluto

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+class Beast
+    function __construct()
+        error("Instantiation not allowed as class is abstract.")
+    end
+
+    function kind() end
+    function name() end
+    function cry()  end
+
+    function print()
+        print($'{self:name()}, who\'s a {self:kind()}, cries: "{self:cry()}".')
+    end
+end
+
+class Dog extends Beast
+    function __construct(private kind, private name) end
+
+    function kind() return self.kind end
+    function name() return self.name end
+    function cry()  return "Woof" end
+end
+
+class Cat extends Beast
+    function __construct(private kind, private name) end
+
+    function kind() return self.kind end
+    function name() return self.name end
+    function cry()  return "Meow" end
+end
+
+local d = new Dog("labrador", "Max")
+local c = new Cat("siamese", "Sammy")
+d:print()
+c:print()