| To implement a Liskov violation with my proposal, you do exactly the same | as with your proposal, *except* that you can simply return None instead | of raising an exception, and the logic for adapt() is more | straightforward.
I think I prefer just returning None rather than raising a specific exception. The semantics are different: None implies that other adaptation mechanisms (like a registry) could be tried, while LiskovException implies that processing halts and no further adaptation techniques are to be used. In this case, None is the better choice for this particular case since it would enable third-parties to register a wrapper.
Overall, I think both you and Alex are now proposing essentially the same thing... no?
Yes; I'm just proposing shuffling the invocation of things around a bit in order to avoid the need for an exception, and in the process increasing the number of possible customizations a bit.
Not that I care about those customizations as such; I just would like to simplify the protocol. I suppose there's some educational benefit in making somebody explicitly declare that they're a Liskov violator, but it seems that if we're going to support it, it should be simple.
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