I think the OP wants something like this: 
#!/your/perl/here

use strict;
use warnings;

my @array1 = qw(dog cat rat mouse);
my @array2 = qw(dog rat mouse bird);
my @array3 = qw(cat rat fish mouse);

my %seen;
my @collection;

foreach my $item ( @array1, @array2, @array3 )
{
    unless ( exists( $seen{$item} ) )
    {
        push @collection, $item;
        $seen{$item}++;
    }
}

print "@collection\n";

__END__

[download]
Which gives: 
dog cat rat mouse bird fish

[download]
I'll leave it to OMAR to come up with an obfuscated compact form.

-QM
--
Quantum Mechanics: The dreams stuff is made of

In reply to Re: "Intelligent" array joining by QM
in thread "Intelligent" array joining by ngomong

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