Inheritance | Object-Oriented JavaScript

object()

Based on the idea that objects inherit from objects, Douglas Crockford suggests the use of an object() function that accepts an object and returns a new one that has the parent as a prototype.

function object(o) {
  function F() {}
  F.prototype = o;
  return new F();
}

If you need access to an uber property, you can modify the object() function like so:

function object(o) {
  var n;
  function F() {}
  F.prototype = o;
  n = new F();
  n.uber = o;
  return n;
}

Using this function will be the same as the extendCopy(): you basically take an object such as twoDee, create a new object from it and then proceed to augmenting the new object.

var triangle = object(twoDee);
triangle.name = 'Triangle';
triangle.getArea = function(){return this.side * this.height / 2;};

The new triangle still behaves the same way:

>>> triangle.toString()

"shape, 2D shape, Triangle"

This pattern is also referred to as prototypal inheritance, because you use a parent object as the prototype of a...

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Object-Oriented JavaScript

Object-Oriented JavaScript

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