Class::Tangram is a common base class originally intended for use with
Tangram objects, that gives you free constructors, access methods,
update methods, and a destructor that should help in breaking circular
references for you.  Type checking is achieved by parsing the Tangram
schema for the object, which is contained within the object class in an
exported variable $schema.

WWW: http://search.cpan.org/dist/Class-Tangram/