The API Reference Scope page says: A scope can inherit from a parent scope. The Developer Guide Scope page says: A scope (prototypically) inherits properties from its parent scope. So, does a child scope always prototypically inherit fr...
This figure again shows that every object has a prototype. Constructor function Foo also has its own __proto__ which is Function.prototype, and which in turn also references via its __proto__ property again to the Object.prototype. Thus, r...
I've been reading "Javascript: The Good Parts" by Douglas Crockford - and while it's a bit extreme, I'm on board with a lot of what he has to say. In chapter 3, he discusses objects and at one point lays out a pattern (also f...
I have a JavaScript function object as; var addNum = function(num1, num2) { return num1 + num2; } Now if I try to access addNum.divide() I wanted to understand the prototype chain for the above code. I read that in the above example,...
I'm seeing posts about a 'new' Object.create that makes enumeration configurable. However, it relies on a Object.defineProperty method. I can't find a cross browser implementation for this method. Are we stuck writing for the o...
I have a situation where I need to check if a constructor (X) has another constructor (Y) in its prototype chain (or is Y itself). The quickest means to do this might be (new X()) instanceof Y. That isn't an option in this case because the const...
I'm building a Node.js app with Connect/Express.js and I want to intercept the res.render(view, option) function to run some code before forwarding it on to the original render function. app.get('/someUrl', function(req, res) { res...
Given simple JS inheritance, what's the practical difference in the base function between these two examples? In other words, when should a person choose to define a function on "this" instead of on the prototype (or the other way around...
This example creates an object, freezes it, and then creates a new object from the frozen object. If the second object tries to change the test property, it can't. It remains frozen with the first object's value of 10. //Create an object and...
I'm trying to get a deeper hold on prototypal inheritance and class creation (I know, there are other ways, but for the purpose of this I'm trying to grasp prototypes.) My question is: Using the following code example, is there a way to creat...
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