Thanks for providing a pure-Perl alternative for deep cloning. Otherwise we are stuck with core module Storable's dclone, which cannot handle Regexp objects out of the box, must use deparse to handle coderefs, and not to mention is not as fast as it should be because it's a marshall+unmarshall algrorithm (ab)used for deep cloning.
Of course, there are faster XS-based cloning modules on CPAN (all currently non-core, believe it or not there are no core modules for cloning except Storable). I'd recommend Data::Clone. But it's nice to have a pure-Perl implementation, e.g. for creating a dependency-free script using App::FatPacker.