++! At the very least, the base class should be setting things up for its children. Also, imho, a base class should also provision for children to add attributes without the child having to know how they're being added. Maybe, some method the child can call in either new or in some bare-block that will add an attribute and mutator or complain if it's a redefinition?

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We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.