#!/usr/bin/perl
use strict;

my $ref1 = [ { key => [ [ "foo" ] ] } ];
my $ref2 = [ [ { key => [ "bar" ] } ] ];
my $ref3 = [ { key => [ [ "baz" ] ] } ];

sub type {
	my $obj = shift;
	my $type;
	
	START:
	if (ref($obj) eq "HASH") {
	    $type .= "oH";
	    $obj = [values(%$obj)]->[0];
	    goto START;
	} elsif (ref($obj) eq "ARRAY") {
	    $type .= "oA";
	    $obj = $obj->[0];
	    goto START;
	}
	$type =~ s/^o//;
	return $type;
}

sub compare {
	my $obj1 = shift;
	my $obj2 = shift;
	
	my $type1 = type($obj1);
	my $type2 = type($obj2);
	
	return $type1 eq $type2 ? 1 : 0;
}

print type($ref1); # Returns AoHoAoA
print compare($ref1, $ref2); # Returns 0
print compare($ref1, $ref3); # Returns 1