JavaScript_Succinctly

var bar = function () {
var goo = function () {
console.log(this); // Logs reference to head window object.
} ();
} ();
} ();
The simple concept here is that functions can be nested and there is no limit to how
deep the nesting can go.
Notes
Remember, the value of this for nested functions will be the head object (e.g., the
window object in a web browser) in JavaScript 1.5, ECMA-262, Edition 3.
Passing functions to functions and returning functions from functions
As previously mentioned, functions are first-class citizens in JavaScript. And since a
function is a value, and a function can be passed any sort of value, a function can be
passed to a function. Functions that take and/or return other functions are sometimes
called "higher-order functions.”
In the following code, we are passing an anonymous function to the foo function which
we then immediately return from the foo function. It is this anonymous function that the
variable bar points to, since foo accepts and then returns the anonymous function.
Sample: sample95.html
// Functions can be sent to, and sent back from, functions.
var foo = function (f) {
return f;
}
var bar = foo(function () { console.log('Hi'); });
bar(); // Logs 'Hi'.
So when bar is invoked, it invokes the anonymous function that was passed to the
foo() function, which is then passed back from the foo() function and referenced from
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