Question

I’ve simulated a static class variable in Javascript.

MyObject.staticVariable = "hello world";

function MyObject() {
    // do something
}

MyObject.prototype.someFunction = function() ...

I do not understand why this syntax works because I do not create MyObject explicitly (and how could I and still have a MyObject function?) before I assign the staticVariable property. But it does work, and I’ve seen it in many answers to the question along the lines of: how do I simulate a static class variable in Javascript?

How can I achieve this functionality when I declare the MyObject function in a namespace?

var Namespace = {};

// Not allowed, and for good reason in my eyes, as NameSpace.MyObject does not exist
Namespace.MyObject.staticVariable = "hello world";

Namespace.MyObject = function() {
    // do something
}

Namespace.MyObject.prototype.someFunction = function() ...

Let me know if I can clarify and/or if my thinking is off. Thanks.

Answer 1

Function declarations are “hoisted” to the top of the current lexical environment.

This means that the function exists before any other code in that environment runs.

// This works

MyObject.staticVariable = "hello world";

function MyObject() {
    // do something
}

---

// This does not

MyObject.staticVariable = "hello world";

var MyObject = function() {
    // do something
}

In your Namespace example, it’s effectively the same as the second example. This means that you’ll needs to make sure the function assignment happens first.