How can I read individual letters of each element to ascertain what is is?

and

How can I tell if the first letter is x, or y?
Those sound like 2 different requirements to me. One quite simple, the other slightly more complex...


1. What are you actually aiming to do?
2. And what does your @foo array actually contain?

Right now, your question is just another XY Problem (pardon the pun)