Yes, I was setting $a and $b. I dumped the result into a string, which was blank, so I assumed the sub was sending back undefined. However, I went back to check for sure, ended up qualifying the call with its package name, and viola it immediately started working. So thanks for the question. :-)

In reply to Re^2: Using sort sub as regular sub by wvbrandt
in thread Using sort sub as regular sub by wvbrandt

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