What is the difference between these functions?

Or here’s from Stefanov’s example:

var result = (function () {
 return 2 + 2;
} ());
(function () {
 alert (‘watch out!’);
}) ();

Answer 1, authority 100%

There is, in general, no difference.
Douglas Crockford found the entry:

(function () {
  // body
} ());

Is correct, and the notation:

(function () {
  // body
}) ();

Wrong and dismissively calling her “dog balls”.

Therefore, use whichever you like best (I, for example, agree with Douglas, although the second option is not annoying at all).
For example, in Perl , the slogan generally states that everything must have several notation paths.
Why is JS worse? 🙂

Answer 2

Corrected code

for (var i = 0; i & lt; 4; i ++) {
(function (i) {setTimeout (() = & gt; console.log (i), 100)} (i))
}

Doesn’t work

((i) = & gt; setTimeout (() = & gt; console.log (i), 100) ( i))

Works

((i) = & gt; setTimeout (() = & gt; console.log (i), 100)) (i)