Logic Bomb... Retrieving "negative" index, and wrap around an Array?

[joshstrike]

Ralgoth your cycle2 has a logical problem...

function cycle2(len:uint,position:int):uint
{
    if(position < 0) position = len + -position;
    return position%len;
}

len = 10
position = -1
position = len + -position == 11
11%10 = 1
but position -1 should correspond to item [9] in the array.

What about:

//edit:
//edit #3. argh:
position = position<0 ? len-(-position%len) : position%len;

///edit: alright I think I finally got it, I'm too wasted to be doing this at 12:30 am...

///edit #47, I think I just reproduced what Moagrius did like six posts ago by trial and error. Just shoot me please.

[Ralgoth]

haha, yeah I didn't get it right until I woke up at 6AM after the whiskey wore off. (most of my friends drunk dial/text... I give drunk coding advice)

it ended up that you cant check if position is a negative, you have to do the modulo first. otherwise if the position is a multiple of the len then the modulo would be 0, and no longer a negative.

the above code would return the array's length (len-(0)).

--- edit --- whiskey goes well w/ coffee.