Sorry if the answer is obvious, I'm still a novice.
Ouch. Quite a task you've got yourself there, for a novice.

I suggest you walk through the code with the debugger, setting breakpoints and gaining familiarity with the code as you go.

At least for me, working with the debugger whenever possible is the best way of finding out what is actualy happening in the program. I've often caught bugs by walking throught the code I wasn't sure of step by step, and comparing the values of the variables with what I thought they should be.

Perl debugger actualy has the functionality you're looking for (in the X command). If you're absolutely decided that you have to implement this for debugging, you can look at the debugger's code to see how it's done.

Good luck!