Two alternative ways derived from: perldoc -q duplicate 

my %seen;
my @uniq = grep { !$seen{$_}++ } keys(%hash1), keys(%hash2);

[download]

use List::MoreUtils qw(uniq);
my @uniq = uniq( keys(%hash1), keys(%hash2) );

[download]

In reply to Re: Syntax explanation required by eyepopslikeamosquito
in thread Syntax explanation required by ghosh123

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