But what if the the classes are intentionally written and maintained with this in mind?

Then I'd ask why you wrote this code as OO, since you aren't getting a major benefit of OO: abstraction.

There are many common approaches for doing the kind of thing you describe that don't require breaking encapsulation. They're so common that they have design pattern names, like "decorator" (wrap one object with another), or "strategy" (delegate the handling of certain methods to different objects determined at runtime). You could also just use the original object's public API to get the data to populate the new objects (a "factory" pattern).

In reply to Re^5: Re-blessing || Re-constructing objects by perrin
in thread Re-blessing || Re-constructing objects by blogical

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