This practice allows your objects to be as flexible with regard to implementation internally as they are to external objects.
Indeed. In particular, it makes a subclass author's life much easier when an object doesn't rely on its own implementation structure any more than absolutely necessary.

Makeshifts last the longest.

In reply to Re^3: InsideOut - even tighter coupling by Aristotle
in thread InsideOut - even tighter coupling by MidLifeXis

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