[ NOT A BUG ] View.as for() loops

[paddy]

hi Cliff,

This isn't a bug but after attending Grant Skinners talk at FOTB. There are some small optimisations you could make to the View.as

:

for (var i:Number = 0; i < observers_ref.length; i++) {
observer = observers_ref[ i ] as IObserver;
observers.push( observer );
}

to

:

var len:int = observers_ref.length
for (var i:int = 0; i < len; ++i) {
observer = observers_ref[ i ] as IObserver;
observers.push( observer );
}

i.e using int instead of Number, moving the length calculation out of loop, using ++i instead of ++i

could go a little way to helping with large apps... Hope all's well, thanks paddy

[puremvc]

length is a property of the observers_ref array which is recalculated by the array whenever items are added or removed (which isn't happening here). Thus our reference to observers_ref.length in the loop condition does no calculation whatsoever so putting it in a separate variable reference before the loop doesn't do anything for us.

And we don't want to use ++i instead of i++ because we don't want to skip the first pass through the loop where i == 0;

-=Cliff>

[paddy]

hi cliff,

That's what I though but ++i doesn't miss first (or last) loop and apprently is slightly more optimal?

:

for (var i:int = 0; i < 10; ++i) {
trace(i)
}

also apprently using int instead of Number in loops has benifical results (perticually for Flash 10):
http://gskinner.com/talks/quick/#10

we're prob only talking about small loops here so this will may not have an effect but wanted to mention it after the talk