Marshall schrieb: > Now, I'm not fully up to speed on DBC. The contract specifications, > these are specified statically, but checked dynamically, is that > right?
That's how it's done in Eiffel, yes. > In other words, we can consider contracts in light of > inheritance, but the actual verification and checking happens > at runtime, yes? Sure. Though, while DbC gives rules for inheritance (actually subtypes), these are irrelevant to the current discussion; DbC-minus-subtyping can still be usefully applied. > Wouldn't it be possible to do them at compile time? (Although > this raises decidability issues.) Exactly, and that's why you'd either uses a restricted assertion language (and essentially get something that's somewhere between a type system and traditional assertion); or you'd use some inference system and try to help it along (not a simple thing either - the components of such a system exist, but I'm not aware of any system that was designed for the average programmer). > Mightn't it also be possible to > leave it up to the programmer whether a given contract > was compile-time or runtime? I'd agree with that, but I'm not sure how well that would hold up in practice. Regards, Jo -- http://mail.python.org/mailman/listinfo/python-list
