#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;

my $a = [ "hello", "day", "sun and fun" ];
my $b = [ 2, "okay", "may" ];
my $c = [ "hello", "day", "sun and fun" ];

my %dup;
my @MyArrayOfArray = grep !$dup{Dumper $_}++, $a, $b, $c;

print Dumper \@MyArrayOfArray;
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Outputs:

$VAR1 = [
          [
            'hello',
            'day',
            'sun and fun'
          ],
          [
            2,
            'okay',
            'may'
          ]
        ];
[download]

Avoids trying to find a unique separator.