I don't see very much Flyweight going on here. You may want to
call your package Class::Privacy. Explanation: You store a scalar
per instance, provided the instance stores a scalar too. No space
saved. The Idea of Flyweight is: Many instances store common values
(mostly arrays and hashes (or records in other languages)),that are related,
as one constant value represented as a pointer (or ref) thereby
saving memory, provided they don't modify the pointed to value.
Modifyability is achieved by not only storing the pointer but overriding
values in the instance too in the hope that many values are common and
only a few must be overridden. An instance can modify its value by
changing the pointer (and possibly choosing appropriate overrides) too.
NOTE: The pointer is not the constant, it's the pointed to value that's constant.
in reply to Class::Flyweight - implement the flyweight pattern in OO perl