1. Create an object called shape that has the type property and a
getType() method.
2. Defne a Triangle() constructor function whose prototype is shape. Objects
created with Triangle() should have three own properties—a, b, and c,
representing the lengths of the sides of a triangle.
3. Add a new method to the prototype called getPerimeter().
4. Test your implementation with the following code:
var t = new Triangle(1, 2, 3); t.constructor === Triangle; //true shape.isPrototypeOf(t); //true t.getPerimeter(); //6 t.getType(); //"triangle"
5. Loop over t showing only own properties and methods (none of
the prototype’s).
6. Make the following code work:
[1, 2, 3, 4, 5, 6, 7, 8, 9].shuffle(); // [2, 4, 1, 8, 9, 6, 5, 3, 7]
Nguồn: Object-oriented JavaScript (S.Stefanov, page 170)
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