I have an action I wish to perform on a bunch of data. However, this action is dependent on the type of data I receive. In order to make this as flexible as possible, I'd like to start out in one class (which has a set of actions it can perform), then be able to rebless into another class should that set of actions be insufficient.

I would caution you to do the following:

• Make sure that the reblessings are in a known tree. In other words, if A doesn't work on X, it will always go to B, not C. If A doesn't work on Y, it goes to C, not B. Make sure that this set of transformations is well-documented.
• Make sure that the set of transformations document above will cover all your possible needs.
• Supply a default error case, which fails out with a useful error message.
• Supply a way to follow the reblessings using some method of logging, even if it's only prints to the screen. Even after debugging the first iteration, leave the debugging in, just in case.
• Make sure that all the classes use the same data structure hierarchy. In fact, I would build a base class, which supplies the attributes, and have the other classes supply the actions. The base class should have all the actions as virtual methods. (For more info, use Super Search or read Perl OO by Damian Conway.

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