Using a mix of prototypal inheritance and copying properties

When you use inheritance, you will most likely want to take already existing functionality and then build upon it. This means creating a new object by inheriting from an existing object and then adding additional methods and properties. You can do this with one function call, using a combination of the last two approaches just discussed.

You can:

  • Use prototypal inheritance to use an existing object as a prototype of a new one
  • Copy all of the properties of another object into the newly created one
    function objectPlus(o, stuff) {
    var n;
    function F() {}
    F.prototype = o;
    n = new F();
    n.uber = o;
    
    for (vari in stuff) {
    n[i] = stuff[i];
    }
    return n;
    }

This function takes an object o to inherit from ...

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