Object-Oriented JavaScript - Third Edition

Exercises

Lets practice the following exercise:

1. Create an object called shape that has the type property and a getType() method.
2. Define 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 your 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, ...