Verifiably better, validated Enum for Python

[Chris Angelico]

On Fri, May 26, 2017 at 9:46 PM, Steve D'Aprano
<steve+python at pearwood.info> wrote:
>
>> And yes, Steve, this is a challenge to you: if you think C's undefined
>> behaviour is an abomination that should not be allowed to exist,
>
> CPython doesn't have to define the behaviour here. In *that* sense, the
> ordinary, regular sense, it is undefined. The implication of that is that
> whatever happens will happen according to some deterministic but
> unpredictable (to you, the developer, at least) chain of cause and effect
> that depends on the implementation. Probably something bad.
>
> That's fine. The Python language does not have to define the behaviour of
> programs which abuse ctypes like that. If you do so, then whatever happens
> will happen.
>
> That's not how the C standard defines "undefined behaviour", or the
> implication of such.

Can you explain to me how it's different? Either way, the
implementation is allowed to do what it likes, because you shouldn't
be doing that.

ChrisA