JavaScript_Succinctly

In the following example, I examine the properties of the window object.
Sample: sample45.html
for (x in window) {
console.log(x); // Logs all of the properties of the window/head
object.
}
You might have noticed that native JavaScript objects are not listed among the host
objects. It’s fairly common that a browser distinguishes between host objects and native
objects.
As it pertains to web browsers, the most famous of all hosted objects is the interface for
working with HTML documents, also known as the DOM. The following sample is a
method to list all of the objects contained inside the window.document object provided
by the browser environment.
Sample: sample46.html
for (x in window.document) {
console.log();
}
What I want you to learn here is that the JavaScript specification does not concern itself
with host objects and vice versa. There is a dividing line between what JavaScript
provides (e.g., JavaScript 1.5, ECMA-262, Edition 3 versus Mozilla's JavaScript 1.6, 1.7,
1.8, 1.8.1, 1.8.5) and what the host environment provides, and these two should not be
confused.
Notes
The host environment (e.g., a web browser) that runs JavaScript code typically provides
the head object (e.g., window object in a web browser) where the native portions of the
language are stored along with host objects (e.g., window.location in a web browser)
and user-defined objects (e.g., the code you write to run in the web browser).
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