We've seen a few means of using references as hash keys. That's pretty cool, from a theoretical standpoint--but I was wondering what the practical application could be.

What are examples of using references as hash keys to make problems easier?

My example, if I wanted to keep a hash of my usernames for websites, and put the prepared HTTP request in the hash. 

use Tie::RefHash;
use HTTP::Request;
use Data::Dumper;

$r1 = HTTP::Request->new(GET => 'http://www.perlmonks.org/');
$r2 = HTTP::Request->new(GET => 'http://use.perl.org/');
# Etc...

tie %sites, 'Tie::RefHash', ($r1, 'Solo', $r2, 'Solo');

print Dumper(\%sites);

[download]

It seems too trivial, but that's probably just my lack of vision ;)

--Solo

--
I think my eyes are getting better. Instead of a big dark blur, I see a big light blur.

In reply to Why use references as keys in a hash? by Solo
in thread using references as keys in a hash. by habit_forming

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