I am trying to add functionality to an add-in by creating my own. Basically
I am going to:

1. Accept a user-entered range
2. Evaluate the formulas to determine if they came from the particular
add-in
3. Use some text evaluation/manipulation to find a position within the
formula and add an argument.
4. Enter this new formula.

The twist is that often times these formulas are array formulas. If the
user selects a range that contains multiple array formulas, or a mix of
array and non-array formulas, I need to be able to isolate each one. Any
ideas on how I accomplish this?