Question

I was fooling around with JS a bit, and I found this:

Anyone care to explain?

Answer 1

An anonymous function is one that doesn’t have a name. For example, you can do:

(function(){ alert("Hello World!") })();

This creates a function with no name and immediately calls it. If the code caused an exception to be raised, the JavaScript runtime will report a failure in an anonymous function.

Also, functions are themselves objects with a class named Function. You can use this class to define a new function like this (instead of the built-in syntax):

(new Function("x", "y", "return x+y"))(1, 2);

This is pretty much the same as writing:

(function(x, y) { return x + y })(1, 2);

This gives you a peek into the object-oriented nature of JavaScript’s functions.