Change $@a->[0] to $a->[0] or $$a[0] (I suggest and prefer the first form). See perlreftut.
Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re: Sort Array Reference by Numeric First Element by japhy
in thread Sort Array Reference by Numeric First Element by awohld

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