A shorter method, which may or may not work, depending on context, is (($x || 0) eq ($y || 0)) However, if 0 is a legitimate value for your code (as it probably is if undef is), you can try to find something that isn't. I'd try something like the default seperator variable ($;), which prints as a weird symbol on my machine.(($x || $;) eq ($y || $;)) If you take the extra spaces out, that's 18 chars.

elusion : http://matt.diephouse.com

Update: This wasn't in response to the hash aspect of the meditation, sorry.