Here is my solution. Although not as in depth, I think it's quite simpler. Expanding it wouldn't be too hard. Right now it only checks for arrays and hashes. 
#!/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

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elusion : http://matt.diephouse.com

In reply to Re: Checking whether two variables have the same structure by elusion
in thread Checking whether two variables have the same structure by Corion

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