Question

The following code does the exact same thing. Is there a difference between for each and for (... in ...)?

var bar:Array = new Array(1,2,3);    

for (var foo in bar){
    trace(foo);
}

for each (var foo2 in bar){
    trace(foo2);
}

Answer 1

No, they do not do the exact same thing.

The output of your for..in loop is

0
1
2

While the output of your for each..in loop is

1
2
3

A for..in loop iterates through the keys/indices of an array or property names of an object. A for each..in loop iterates through the values. You get the above results because your bar array is structured like this:

bar[0] = 1;
bar[1] = 2;
bar[2] = 3;