I coulda sworn I had blogged this earlier but it didn't show up on my search. This just came up in a meeting at work so I thought I'd share. ColdFusion 8 added the arrayIsDefined function. As you can probably guess it let's you check to see if an array has a value at a certain position. However, it had one pretty silly drawback. If your array was had a size of 10 and you checked position 11, you would get an error. Therefore to really check to see if a certain array position existed, you had to use this:
<!--- assume array is called arr and N is the position you want to check ---> <cfif arrayLen(arr) gte n and arrayIsDefined(arr, n)>
ColdFusion 9 though fixes this. So your code can just be:
<!--- assume array is called arr and N is the position you want to check ---> <cfif arrayIsDefined(arr, n)>
Oddly, the docs for arrayIsDefined still insist that you must stay within the bounds of the array. I'm filing a comment now.