What is the purpose of a self executing function in javascript?

Question

In javascript, when would you want to use this:

(function(){
    //Bunch of code...
})();

over this:

//Bunch of code...
         


        

Answer 1

Scope isolation, maybe. So that the variables inside the function declaration don't pollute the outer namespace.

Of course, on half the JS implementations out there, they will anyway.