After some brief "research", I saw this brief description of the Liskov Substitution Principle:
Let q(x) be a property provable about objects x of type T. Then q(y) should be true for objects y of type S where S is a subtype of T.
And I filled in the variables, and tried to figure out if the following violates the LSV, and is therefore a bug by your reasoning:
Let is_red(x) be a property provable about objects x of type FireEngine. Then is_red(y) should be true for objects y of type YellowFireEngine where YellowFireEngine is a subtype of FireEngine.

It just seems like the above is something you might want to do...override some attribute in a sub-type, yet Liskov won't let me do it. I guess I'm glad perl doesn't enforce the Liskov Substitution Principle...or am I completely misunderstanding?

In reply to Re^2: Attempt to uninherit method by runrig
in thread Attempt to uninherit method by runrig

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