It's not an error, it's a warning. But yes, it's saying that $line (and thus, $source[2]) is uninitialized. You should probably check to see if there's anything in @source before you use it.
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: Completely lost - 'Use of uninitialized value in pattern match...' error :( by japhy
in thread Completely lost - 'Use of uninitialized value in pattern match...' error :( by n00dles

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