I do wonder why in the refaddr code in non-XS Scalar::Util, the code stringifies the reference then pulls a number out with a regex. As far as I can tell in terms of complexity and time-efficiency, that's clearly inferior to forcing the reference to numeric.

http://groups.google.com/group/perl.perl5.porters/browse_thread/thread/6b393e4e2c3652d5/945f809ee3431bc0#945f809ee3431bc0