JavaScript, which of these two is better?

Question

I think (if I am not wrong), that when using && operator, the second parm will not even execute when the first evaluated to false.

So It would be wise to put the parm that will be more likely to be false at first, right?

When looping, like this:

function inArray(fnd,arr){
    var i=0,ien=arr.length;
    for(;i<ien;i++){
        if(i in arr&&arr[i]===fnd){
            return i;
        }
    }
    return -1;
}

---

Which would be better to use?

...
if (i in arr && arr[i] === fnd) {
    return i;
}
...

or

...
if (arr[i] === fnd && i in arr) {
    return i;
}
...

Answer 1

Why are you using (i in arr) anyway? You already know it returns true, since you're not iterating out of the bounds of the array. if (arr[i] === fnd) return i; should be enough

Answer 2

The first one is the only of those two that makes any sense.

In the second one you are first accessing the array, then checking if you can access the array, so the check is pointless.