Extending Zymonic with polymorphism (sub-classing)

In general sub-classing is done by copying the existing class e.g. Zymonic/Field.pm into the appropriate sub-directory (Field) with a new name e.g. Zymonic/Field/MySubClass.pm, changing the package name, the content of the POD and removing all the methods from the original file apart from any you intend to modify.

However, there are some cases that warrant further discussion: