Accoring to the documentation for sort, it expects a function that returns -1, 0, or 1 for (a<b),(a==b),(a>b), respectively. So, that's all your sub needs to do.
Actually, according to your link:
SUBNAME ... gives the name of a subroutine that returns an integer less than, equal to, or greater than 0
which is rather less stringent than requiring -1, 0 or 1.

Roger

In reply to Re^2: sort direction by Roger_B
in thread sort direction by rsiedl

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