iife - A Javascript function

Question

Please explain the following way of writing a function in javascript functions :

(function (){
 // some code 
})()

I understand the fact that because of the trailing braces " () ", the function will execute immediately but but what does enclosing the function in the braces mean?

Answer 1

As RobG pointed out, this is the only valid statement choice in your original question.

(function (){
 // some code 
}())

This is executed right after it is parsed, and provides a way to out-scope the code inside the function from the rest of your code. This is called a closure (see Closures on MDN) and may help with memory leaks in your scripts.