module for recursively copying Perl datatypes

 The Clone module provides a clone() method which makes recursive copies of
 nested hash, array, scalar and reference types, including tied variables and
 objects.
 .
 It is faster (although less flexible) than Storable's dclone. Its
 functionality is _not_ serializing in-memory objects (i.e. as
 Data::Dumper or YAML::Dump do), but deep-copying them over to new
 in-memory structures.