Might be that you are using an older version of Perl? I'm on 5.16. Here is a two line version: 

my %seen =  map { $_ => 1 } split /\n/, $match;
my @r = keys %seen;

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Hope this now works for you. And I still assume that you want to get rid of the \n? Apologies for any confusion I caused.

In reply to Re^3: Removal of duplicated element in array. by hdb
in thread Removal of duplicated element in array. by tty1x

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