Your post is an excelent example of why inheirtance relationships are so hard to get right (even for this seemingly trivial example). From a Eucldian point of view, a square ISA rectangle. However, in OOP, a subclass is supposed to extend the parent's behavior, so it makes more sense to say a rectangle ISA square. Two groups thus create two opposite designs.

So who is right? It depends on your application. As you say, if this is a program for geometry, it's probably better to say a square ISA rectangle. If it's a CAD program, then it's probably better to say a rectangle ISA square.

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send money to your kernel via the boot loader.. This and more wisdom available from Markov Hardburn.

In reply to Re^3: When are packages the right design choice? by hardburn
in thread When are packages the right design choice? by fuzzyping

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