Initial data commit

Task/Polymorphic-copy/Wren/polymorphic-copy.wren

@@ -0,0 +1,33 @@
+class Animal {
+    construct new(name, age) {
+        _name = name
+        _age = age
+    }
+
+    name { _name }
+    age  { _age }
+
+    copy() { Animal.new(name, age) }
+
+    toString { "Name: %(_name), Age: %(_age)" }
+}
+
+class Dog is Animal {
+    construct new(name, age, breed) {
+        super(name, age) // call Animal's constructor
+        _breed = breed
+    }
+
+    // name and age properties will be inherited from Animal
+    breed { _breed }
+
+    copy() { Dog.new(name, age, breed) } // overrides Animal's copy() method
+
+    toString { super.toString + ", Breed: %(_breed)" } // overrides Animal's toString method
+}
+
+var a = Dog.new("Rover", 3, "Terrier") // a's type is Dog
+var b = a.copy() // a's copy() method is called and so b's type is Dog
+System.print("Dog 'a' -> %(a)") // implicitly calls a's toString method
+System.print("Dog 'b' -> %(b)") // ditto
+System.print("Dog 'a' is %((Object.same(a, b)) ? "" : "not") the same object as Dog 'b'")